Add a job to sync github repo with Codehub

[pratikvn]

This PR adds a github sync workflow to sync the github repo to codehub when the main/develop/release branches have been updated for easy CI/CD within the CASTIEL-2 project.

The objective is that eventually Ginkgo will be automatically deployed on the EU supercomputers and available to users through Easybuild and EESSI

[yhmtsai]

we only sync our code to their side. Do we need to provide any compilation step here?

[pratikvn]

@yhmtsai , currently, I only sync. The compilation is done with easybuild, so that will be handled externally. In a fashion similar to spack.

[yhmtsai]

Does anyone else have access to the documentation? maybe @fritzgoebel ?
does the sync only syncs the branch which triggers the event or the entire repo? probably the entire repo because you set the fetch-depth 0

[pratikvn]

I think syncing the whole repo should not be an issue. We might want to trigger specific branches and/tags, and I believe there should be no specific downside to syncing all the branches and tags.

[yhmtsai]

No, I do not mean avoiding sync the entire repo.
more on checking which one is what you would like to do because the pr description sounds more on only push certain branch not entire one.

[yhmtsai]

I do not know the usage of arguments from git-repo-sync from CASTIEL2
Others look good to me

[pratikvn]

I have updated the description.