oc_config_validate is pinned to Python 3.9 due to pyanbdind

[JoseIgnacioTamayo]

https://pypi.org/project/pyangbind/

pyanbdind is a dependency of oc_config_validate. pyanbdind uses collections.MutableSequence, which after Python 3.10 is moved to collections.abc.MutableSequence

Until pyanbdind's code is updated, oc_config_validate can only work on Python 3.9

If you have Python 3.10, you can install and run oc_config_validate, after locally patching robshakir/pyangbind#291

[JoseIgnacioTamayo]

This has been solved in recent versions of pyangbind.