GitHub Action to automatically create a PR to main

[alvarof2]

Description

GitHub Action to automatically create a PR when *-docs branches are updated by the component's own GA. E.g. gateway repo GA will push changes in docs to gateway-docs branch in this repo, which will create a PR for revision.

Is this PR related with an open issue?

Related to Issue engineering #51

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [ ] Follows the code style of this project.
• [ ] Tests Cover Changes
• [x] Documentation