Allow full Issue URLs and all GitHub recognized Issue reference keywords in PR body validation

[Relequestual]

Currently, the PR Body Validation workflow only accepts issue references in the form "closes #1234" or "related to #1234". However:

• GitHub itself recognizes full URLs as valid issue references (e.g., "closes ✨ Enhancement: Improve the design of the Community page #1234").
• GitHub also supports a variety of keywords to link PRs to issues, such as "fixes", "resolves", "implements", "addresses", etc. (See: https://docs.github.com/en/issues/tracking-your-work-with-issues/linking-a-pull-request-to-an-issue)

Expected resolution:

Update the PR Body Validation workflow to accept:

• Full URLs to issues (not just the #1234 format).
• Any of the official GitHub-recognized keywords for issue references.

This would make PR validation consistent with GitHub’s own behavior and reduce friction for contributors who use the full range of supported formats.

[Utkarsh-123github]

Hi @Relequestual , I would be glad to work on this. Kindly assign this to me at your convenience.
Thank You!

[vtushar06]

Hi @Relequestual @Utkarsh-123github ,
I would love to contribute to this issue. Could you please assign it to me?
Thanks in advance!