Define procedure for the repository synchronisation (GitLab-to-GitHub)

It was defined a push mirror repository from CAiMIRA's GitLab to GitHub to profit from external contributions (general, non-CERN).

It was also defined a push mirror repository from CAiMIRA's GitLab to Azure DevOps. The idea is that the mirror repository on DevOps is imported as a submodule on the ARIA Project.