changed docs paths to relative & gh action

[petercrocker]

Previously the docs had absolute paths in them, which won't work when syncing them to the infrahub-docs repo. Changed all absolute to relative paths.

Added GitHub action to sync docs to infrahub-docs when changes are made to the docs/docs, docs/media or docs/sidebar.ts files.

[BeArchiTek]

I start adding some comment, I think we could simplify some Paths as we are using relative ones.

Not mandatory.

For the rest LGTM