Can/should/must we switch away from CERN Gitlab?

[GitLab issue: #717](https://gitlab.cern.ch/acts/acts-core/issues/717)

# Arguments

Non-exhaustive list of pro/contra arguments.

## For staying with CERN Gitlab

* Gitlab is fully integrated and handles the repos, issues, and the CI
* Hosted at CERN with dedicated support and infrastructure; does not rely on free-tier of external services.

## Against staying with CERN Gitlab

* Easier participation of non-CERN users.
* External services can provide more functionality then what is available with Gitlab

# Requirements for another hosting solution

A non-exhaustive list of functionality that we need to host the Acts development in addition to hosting just the git repository.

* Issue tracker
* CI builds with runners that can access CVMFS (to test with LCG releases)
* Sufficient resources to run our extensive builds and unit tests
* Possibility to run multi-threaded tests
* ...

Start by reviewing the linked GitLab issue #717 and the arguments and requirements in this issue. Compare potential hosting options against the required issue tracker, CI runners with CVMFS access, build resources, and multi-threaded test support. Done means reaching and recording a decision about whether to stay with CERN GitLab or switch.

Escrita pelo modelo de indexação a partir do texto da issue.