Document correct settings for Docker Desktop for Mac

[martinmo]

The test test_kill_on_timeout reliably fails on macOS, I'm not sure when this started to appear because I normally only execute the test suite with --exclude-tag=slow.

======================================================================
FAIL: test_kill_on_timeout (tests.testrunner.tests.DockerTestRunnerIntegrationTest)
Test if the container gets killed after the timeout.
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/martin/Code/inloop/inloop/tests/testrunner/tests.py", line 69, in test_kill_on_timeout
    self.assertLess(result.duration, 10.0)
AssertionError: 10.838416578 not less than 10.0

----------------------------------------------------------------------
Ran 222 tests in 39.785s

FAILED (failures=1)

Normally this test should take less than a second and the whole test suite less than 15 seconds.

I guess this is a behavorial change in Docker Desktop for Mac that invalidated some assumptions in our testrunner code. Versions:

$ python --version
Python 3.7.9
$ docker --version
Docker version 20.10.2, build 2291f61
$ sw_vers
ProductName:    Mac OS X
ProductVersion: 10.15.7
BuildVersion:   19H114

However, the tests on Travis CI, under Linux, pass.

[martinmo]

Turns out that disabling the experimental "cloud experience" feature in the docker settings resolves this issue (it is on by default).

Thus, this bug turns into a documentation enhancement.

[martinmo]

Closing this as this setting ("cloud experience") disappeared from the Docker for Mac configuration.