Reenable flake8-pyi's Y011 and Y015

[AlexWaygood]

Cc. @Avasam for PyScreeze and pywin32; cc. @hmc-cs-mdrissi for TensorFlow.

Following the new release of flake8-pyi, default values for parameters are allowed in many situations. The new rules are that default values are allowed if the default value is an int, a float, a complex number, a string, a bytes object, a bool, None, or ....

For other default values, we'll continue to use .... This has two advantages:

• It keeps stubs concise and readable.
• It means that stubtest will be easily able to verify any default values that we do include in the stubs, something which it might struggle with if we were to include more complex default values.

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉

[hmc-cs-mdrissi]

Tensorflow side looks good to me. I'll miss enums a bit, but I can see understanding enums would likely be too complex for a static checker like flake8-pyi

[Avasam]

Awesome. I was waiting for this to be fully supported to update the stubs I contributed and use.