Support Python 3.10

[jiasli]

Description

Python 3.10 has been released on 2021-10-04: https://www.python.org/downloads/

Azure CLI needs to support Python 3.10 like how we supported 3.9 (#16611).

TODOs

• Knack supports Python 3.10: Support Python 3.10 microsoft/knack#250
• azdev supports Python 3.10: Support Python 3.10 azure-cli-dev-tools#319
• CI passes with Python 3.10
  • Dependencies like pytest, pylint are updated to the Python 3.10 compatible version: {Pylint} Adapt to Pylint 2.11.1 #20192
  • New pylint check failures are fixed or ignored: {Pylint} Adapt to Pylint 2.11.1 #20192
  • All test cases pass: [Packaging] Support Python 3.10 #20195

[yonzhan]

Python 3.10 support

[miqm]

@jiasli - will the Docker image be upgraded to python 3.10.x? currently is 3.9.6 (which is not the latest one though)

[jiasli]

@miqm, actually we use Python 3.8 in DEB package and Windows MSI, and Python 3.6 in RPM. 😅

Are there any absolute needs to use Python 3.10 in the docker image? I can certainly prioritize it if they are reasonable.

[miqm]

@jiasli - It's not a must, however often people use the CLI image in CI/CD systems and some new custom-made scripts might benefit from newer python features.

In general it would be awesome if you produce a series of azure-cli docker tags so people could choose which kind of base image they would like to use (i.e. python3.9-slim-bullseye, python3.8-alpine, etc.)

[jiasli]

@miqm, this is a good suggestion. I have created #21074 to track it.

[jiasli]

@miqm, upgrading to Python 3.10 in #21079.