Enable 'Public function Missing Docstrings' PyDocStyle Check

[kaxil]

This is one of the important checks I wanted to enable.

After this hopefully, everyone would document all public functions

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• Description above provides context of the change
• Unit tests coverage for changes (not needed for documentation changes)
• Target Github ISSUE in description if exists
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• Relevant documentation is updated including usage instructions.
• I will engage committers as explained in Contribution Workflow Example.

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