Ingestion example does nothing (no failures, no success)

Code Sample, a copy-pastable example if possible

I'm directly following the ingest example, focusing on the Pandas ingest example, because it is self-contained.

I think I've gotten the authentication part right, at least I'm not getting any errors.

I have set report_level=ReportLevel.FailuresAndSuccesses.

Problem description

The problem is that nothing happens on ingestion. During the ingestion status monitoring I'm getting:

No new messages. backing off for 2 seconds
No new messages. backing off for 4 seconds
No new messages. backing off for 8 seconds
No new messages. backing off for 16 seconds
No new messages. backing off for 32 seconds
No new messages. backing off for 64 seconds
No new messages. backing off for 128 seconds
No new messages. backing off for 180 seconds
...

which suggest that both qs.success.is_empty() and qs.failure.is_empty() are empty.

This is my very first step with ADX, which is why I have no idea how to debug the problem.

If query related, does it happen on other platforms (Kusto Web UI, Kusto Explorer)?

N/A

Output of `pip freeze`

``` absl-py==0.9.0 actionlib==1.11.13 adal==1.2.4 angles==1.9.12 ansi2html==1.5.2 ansible==2.9.10 anytree==2.8.0 apipkg==1.5 argh==0.26.2 artifactory==0.1.17 asammdf==5.20.6 asgiref==3.2.10 astor==0.8.1 attrs==19.3.0 avro==1.9.2 avro-python3==1.10.0 azure-core==1.6.0 azure-identity==1.4.0 azure-kusto-data==1.0.2 azure-kusto-ingest==1.0.2 azure-storage-blob==12.3.2 azure-storage-queue==12.1.2 bidict==0.19.0 bitstruct==8.11.0 bokeh==2.1.1 boolean.py==3.4 bottle==0.12.18 cachetools==4.1.1 cachier==1.2.8 camera-calibration-parsers==1.11.13 canmatrix==0.9.1 cassandra-driver==3.24.0 catkin==0.7.20 catkin-pkg==0.4.22 cchardet==2.1.5 certifi==2020.6.20 cffi==1.14.0 chardet==3.0.4 click==7.1.2 cloudpickle==1.5.0 cmake==3.17.3 colorama==0.4.3 coloredlogs==14.0 conan==1.27.0 confluent-kafka==1.4.1 coverage==5.2 croniter==0.3.34 cryptography==2.9.2 cv-bridge==1.12.8 cycler==0.10.0 dask==2.20.0 decorator==4.4.2 defusedxml==0.6.0 deprecation==2.0.7 diagnostic-updater==1.9.3 dill==0.3.2 dirhash==0.2.0 distributed==2.20.0 distro==1.1.0 Django==3.0.8 django-emoji==2.2.2 django-filter==2.3.0 django-mathfilters==1.0.0 django-safedelete==0.5.5 djangorestframework==3.11.0 docker==4.2.2 docopt==0.6.2 docutils==0.16 dynamic-reconfigure==1.5.50 elasticsearch==7.8.0 empy==3.3.4 entrypoints==0.3 evaluation-api-client==1.0+72379a1e execnet==1.7.1 fasteners==0.15 filelock==3.0.12 flake8==3.8.3 Flask==1.1.2 Flask-Cors==3.0.8 Flask-PyMongo==2.3.0 fsspec==0.7.4 ftfy==4.4.3 future==0.18.2 gast==0.2.2 gcovr==4.2 gencpp==0.6.0 geneus==2.2.6 genlisp==0.4.16 genmsg==0.5.11 gennodejs==2.0.1 genpy==0.6.7 geographiclib==1.50 geojson==2.5.0 geomet==0.2.1.post1 geopy==2.0.0 gitdb==4.0.5 gitdb2==2.0.6 GitPython==3.1.3 google-auth==1.18.0 google-auth-oauthlib==0.4.1 google-pasta==0.2.0 graphviz==0.14 grpcio==1.28.1 h5py==2.10.0 HeapDict==1.0.1 html5lib==1.1 humanfriendly==8.2 idna==2.10 image-geometry==1.12.8 importlib-metadata==1.7.0 interactive-markers==1.11.4 ipython==5.10.0 ipython-genutils==0.2.0 isodate==0.6.0 itsdangerous==1.1.0 jenkinsapi==0.3.11 Jinja2==2.11.2 jira==2.0.0 joblib==0.16.0 jsk-recognition-utils==1.2.9 jsk-rviz-plugins==2.1.5 jsk-topic-tools==2.2.10 jwt==0.6.1 Keras==2.3.1 Keras-Applications==1.0.8 Keras-Preprocessing==1.1.0 kiwisolver==1.2.0 kubernetes==11.0.0 laser-geometry==1.6.4 llvmlite==0.31.0 locket==0.2.0 lxml==4.5.1 lz4==3.1.0 maploc-gcovr==4.1 Markdown==3.2.1 MarkupSafe==1.1.1 marshmallow==3.7.1 marshmallow-oneofschema==2.0.1 matplotlib==3.2.2 mccabe==0.6.1 message-filters==1.12.14 mock==4.0.2 mongomock==3.19.0 monotonic==1.5 more-itertools==8.4.0 mpld3==0.5.1 mplleaflet==0.0.5 msal==1.4.3 msal-extensions==0.2.2 msgpack==1.0.0 msrest==0.6.17 multiprocess==0.70.10 mypy-extensions==0.4.3 mysql-connector-python==8.0.20 natsort==7.0.1 netifaces==0.10.9 networkx==2.4 node-semver==0.6.1 nose==1.3.7 numba==0.47.0 numexpr==2.7.1 numpy==1.19.0 numpy-quaternion==2019.12.11.22.25.52 oauthlib==3.1.0 opt-einsum==3.2.1 overpass==0.7 packaging==20.4 pandas==0.25.3 partd==1.1.0 patch-ng==1.17.4 pathlib==1.0.1 pathlib2==2.3.5 pathos==0.2.6 pathspec==0.8.0 pathtools==0.1.2 pbr==5.4.5 pendulum==2.1.2 perfect==0.0.1 pexpect==4.8.0 pick==0.6.7 pickleshare==0.7.5 Pillow==7.2.0 pip-tools==5.2.1 plotly==4.8.2 pluggy==0.13.1 pluginbase==0.7 pluginlib==1.11.3 portalocker==1.7.0 pox==0.2.8 ppft==1.6.6.2 prefect==0.12.6 progressbar==2.5 progressbar2==3.51.4 prompt-toolkit==1.0.18 protobuf==3.12.2 psutil==5.7.0 psycopg2==2.8.5 ptyprocess==0.6.0 py==1.9.0 pyarrow==0.17.1 pyasn1==0.4.8 pyasn1-modules==0.2.8 pybind11==2.5.0 pycodestyle==2.6.0 pycparser==2.20 pyflakes==2.2.0 Pygments==2.5.2 PyJWT==1.7.1 pymap3d==1.6.3 pymongo==3.10.1 PyMySQL==0.9.3 pyodbc==4.0.30 pyparsing==2.4.7 pypcd==0.1.1 pyproj==2.6.1.post1 pyros==0.4.3 pyros-common==0.5.4 pyros-config==0.2.1 pyros-setup==0.3.0 pyrosbag==0.1.3 pyserial==3.4 pysolr==3.9.0 pytest==5.4.3 pytest-cov==2.10.0 pytest-forked==1.2.0 pytest-mock==3.1.1 pytest-timeout==1.4.1 pytest-watch==4.2.0 pytest-xdist==1.32.0 python-box==4.2.3 python-dateutil==2.8.1 python-intervals==1.10.0.post1 python-lzf==0.2.4 python-qt-binding==0.3.4 python-slugify==4.0.1 python-utils==2.4.0 pytz==2020.1 pytzdata==2020.1 PyYAML==3.13 pyzmp==0.0.17 pyzmq==19.0.1 qt-dotgraph==0.3.11 qt-gui==0.3.11 qt-gui-cpp==0.3.11 qt-gui-py-common==0.3.11 redis==3.5.3 requests==2.24.0 requests-oauthlib==1.3.0 requests-toolbelt==0.9.1 resource-retriever==1.12.5 retry==0.9.2 retrying==1.3.3 rosbag==1.12.14 rosclean==1.14.6 rosdep==0.19.0 rosdistro==0.8.2 rosgraph==1.12.14 roslaunch==1.12.14 roslib==1.14.6 roslint==0.11.0 roslz4==1.12.14 rosmake==1.14.6 rosmaster==1.12.14 rosmsg==1.12.14 rosnode==1.12.14 rosparam==1.12.14 rospkg==1.2.8 rospy==1.12.14 rosservice==1.12.14 rostest==1.12.14 rostopic==1.12.14 rosunit==1.14.6 roswtf==1.12.14 rqt-bag==0.4.12 rqt-console==0.4.9 rqt-graph==0.4.11 rqt-gui==0.5.0 rqt-gui-py==0.5.0 rqt-image-view==0.4.14 rqt-logger-level==0.4.8 rqt-plot==0.4.8 rqt-py-common==0.5.0 rsa==4.6 ruamel.yaml==0.16.10 ruamel.yaml.clib==0.2.0 rviz==1.12.17 scantree==0.0.1 scikit-learn==0.23.1 scipy==1.5.1 sensor-msgs==1.12.7 sensoris==1.1.0 sentinels==1.0.0 Shapely==1.7.0 simplegeneric==0.8.1 simplejson==3.17.0 six==1.14.0 sklearn==0.0 smclib==1.8.3 smmap==3.0.4 smmap2==2.0.5 sortedcontainers==2.2.2 sound-play==0.3.3 sqlitedict==1.6.0 sqlparse==0.3.1 tables==3.6.1 tabulate==0.8.7 tblib==1.6.0 tensorboard==2.1.1 tensorflow==2.1.0 tensorflow-estimator==2.1.0 termcolor==1.1.0 text-unidecode==1.3 tf==1.11.9 tf-conversions==1.11.9 tf2-geometry-msgs==0.5.20 tf2-kdl==0.5.20 tf2-py==0.5.20 tf2-ros==0.5.20 Theano==0.9.0 threadpoolctl==2.1.0 toml==0.10.1 toolz==0.10.0 topic-tools==1.12.14 tornado==6.0.4 tqdm==4.47.0 traitlets==4.3.3 turbodbc==4.0.0 typing-extensions==3.7.4.2 urdfdom-py==0.3.3 urllib3==1.25.9 uwsgidecorators==1.1.0 watchdog==0.10.3 wcwidth==0.2.5 webencodings==0.5.1 websocket-client==0.57.0 Werkzeug==1.0.1 wrapt==1.12.1 zict==2.0.0 zipp==3.1.0 ```

Azure / azure-kusto-python