fix(ci): use auto mode for pytest-asyncio (backport #3959) (#3964)

* fix(ci): use auto mode for pytest-asyncio (#3959)

pytest-asyncio changed the default mode to strict in 0.19 which breaks
most of our asyncio related integrations.

https://github.com/pytest-dev/pytest-asyncio/blame/v0.19.0/CHANGELOG.rst#L7

We have to explicitly set this mode to `auto` to keep the same
functionality we had prior to the 0.19 release.

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>
(cherry picked from commit da89b44)

Co-authored-by: Kyle Verhoog <[email protected]>

Author: mergify[bot]

tox.ini

@@ -275,3 +275,4 @@ python_files = test*\.py
 filterwarnings =
     # Show any DeprecationWarnings once
     once::DeprecationWarning
+asyncio_mode = auto