.gitlab/issue_templates/*:
Replace allan with grazzolini when assigning tickets or when addressing
main key holders.
Streamline the checkbox system, by relying on less interaction from the
main key holders side if possible (e.g. checks on new keys are done
automatically in a merge request, so have contributors open the merge
request).
Add more documentation on what needs to be edited and how to provide
data exactly (e.g. keyid format, clearsigned document).