enable only docs workflow when changes made to md files

[rvarun11]

When changes are made to markdown files all workflows are run. Ideally, in such a scenario we should only run the the docs workflow. We can do so by using something like this on all other workflows:

on:
  push:
    paths:
      - '**/*'
      - '!**/*.md'  # Exclude Markdown files

Thoughts?