Run Tests Against Python 3.10

[grant]

Expected Behavior

Unit tests are run against python310. This would be nice to have as we're developing a runtime that uses

Actual Behavior

Unit tests don't run against 3.10

appengine-python-standard/.github/workflows/unit.yml

Line 16 in 6ea19dd

python: [3.7, 3.8, 3.9]

CC: @shreejad @asriniva

[shreejad]

Will the expected behavior be that these unit tests keep failing till the release is complete? And then it is used as one of the success criteria? Just confirming.

[asriniva]

The unit tests run off the public version of Python 3.10, so they should be passing now. We should be able to just add this to the version matrix.

[asriniva]

Turns out ruamel.yaml doesn't support Python 3.10 yet, so we're waiting on that.