Describe the bug
The GitLab CI template from R2Devops as recommended by megalinter doesn't exist anymore.
This caused our megalinter CI jobs to fail hard. The following snippet results in an invalid YAML, since the server responds (currently) with a 503 error code.

include:
  - remote: 'https://api.r2devops.io/api/r/gitlab/r2devops/hub/mega_linter@3.0.0.yaml'

To Reproduce
Steps to reproduce the behavior:

1. Go to https://megalinter.io/latest/install-gitlab/
2. Click on https://r2devops.io/marketplace/gitlab/r2devops/hub/mega_linter

Expected behavior
Megalinter should no longer recommend R2Devops template, or at least point to the archived repository (see below).

Screenshots

Additional context
The GitLab template is (currently) available on gitlab.com.
However, that repository is archived and no longer maintained.