ci: fix and improve automation around MAINTAINERS.yaml

[aeworxet]

This PR is a work in progress.

Related to #1620

[aeworxet]

I tried nearly every option specified in the GitHub Docs, both with fine-grained and legacy tokens, but

• with github-token specified I get Error: Input required and not supplied: github-token

• without github-token specified and using any other method of authentication I get Resource not accessible by integration

The property permissions, neither with actions: write nor with write-all, has no effect in any place of the workflow.

The request itself successfully executes manually with header

Authorization: token token_specified_as_GH_TOKEN_in_GH_Actions

so there is no mistake in it.

@derberg, do you have ideas on what else could be researched?

[Shurtu-gal]

@aeworxet If it is working manually then there is some problem in the workflow itself.

Could you try passing secrets.GH_TOKEN to github-token itself?

You could try this endpoint as well https://docs.github.com/en/rest/orgs/members?apiVersion=2022-11-28#create-an-organization-invitation

Also better would be to use their calls itself instead of raw API calls.https://octokit.github.io/rest.js/v21/#orgs-create-invitation