License headers are missing for docs and other .md files

[parshimers]

Task Summary

The docs and other .md files are missing ASL license headers. This is because the CI was allowlisting any .md file against license header checks. The proper headers should be added and the filter on the CI tightened.

Task Type

• Refactor / Cleanup
• DevOps / Deployment / CI
• Testing / QA
• Documentation
• Performance
• Other

[github-actions]

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