As a doc-only contributor I would like to have the full CI skipped

[pedro-psb]

Is your feature request related to a problem? Please describe.
When contributing doc-only changes, the full CI is unnecessarily triggered, which is a waste of time and resources.

Describe the solution you'd like
Following up on the doc-workgroup discussions around making doc contributions smooth, it would be nice if doc-only changes would not trigger the full CI test suite.

By "doc-only changes" I mean a PR in which all the affected files belong to the docs folder (or some similar safe-filter strategy).

Describe alternatives you've considered
None.

Additional context
If that helps, I've done something similar in dynaconf here (based on github docs).