Deprecate PY* constants into the airflow module

[Taragolis]

First constant was added in #7517 for validate is Airflow run on Python >= 3.7 and if not use backport support of PEP-562.

It is not widely use in Airflow Core, at that moment there is only one reference. However it might be not safe to use it in core, because it might create cyclic error in case if it imported somewhere else during first load, e.g. into the airflow.configurations or airflow.settings or their imports. In providers it is not practical to use it, you have to wait approx one year for allow to use it, and it also might be a reason for cyclic errors, e.g. if it use in secrets backends and their imports.

For avoid usage in project it disabled by TID251 - Banned API
All current usage, most in tests, replaced by sys.version_info

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[Taragolis]

I do not delete this constants for two reason:

• Maybe some old version of provider still use it
• Maybe some users use it, which is not practical

[hussein-awala]

LGTM