Fix tests, CI badge, make tests run faster

[oraclown]

These tests are failing (for akrem):

• [x] tests/reporters/test_custom_360_reporter.py::test_submit_once
• [x] tests/reporters/test_polygon_reporter.py

[oraclown]

Reporter tests failing on my local:

==================================================================== short test summary info ====================================================================
FAILED tests/reporters/test_360reporter.py::test_report - assert 0 == 1000000000000000000
FAILED tests/reporters/test_360reporter.py::test_adding_stake - assert False
FAILED tests/reporters/test_360reporter.py::test_no_native_token - assert 'insufficient native token funds' in "info     telliot_feeds.reporters.tellor_360:te...
FAILED tests/reporters/test_custom_360_reporter.py::test_submit_once - AssertionError: assert False
FAILED tests/reporters/test_polygon_reporter.py::test_fetch_gas_price_error - AssertionError: assert 'Invalid gas price speed for matic gasstation: blah' in '...
FAILED tests/reporters/test_rng_reporter.py::test_report - assert "Unable to stake deposit: Send transaction failed: ValueError({'message': 'VM Exception whil...
====================================================== 6 failed, 32 passed, 1 warning in 115.35s (0:01:55) ======================================================

looks like tests/reporters/test_360reporter.py::test_no_native_token fails when run with the group, but not alone

[oraclown]

Another thing:

• [x] make it not ask for a Rinkeby account when you run tests locally
• [x] ensure all tests pass locally when running tox

[oraclown]

To do:

• [ ] CI runs pass even though some tests might fail
• [ ] Remove CodeCov or fix it. this and this
• [ ] Entire test suite takes like minutes to run. Make faster so dev workflow isn't painful