The general workflow should be to create a branch (either directly in this repository or in a clone/fork), do your changes, commit and create a merge request for review. This gives other team members the possibility to notice and review your changes. It even sends out Emails, so other team members become aware of them.
On the other side, we do not want to block anyone from being productive. So here are the general rules:
Always use merge requests.
We allow to merge those requests on your own - but we want to make use of the benefits of merge requests (notifications, tests, visibility).
Merge requests that require a review:
changes that might affect a bigger amount of machines - especially, if this affects machines maintained by others
potentially dangerous stuff that might break existing setups
Merge requests that could be self-merged:
emergency updates repairing something that is already broken (think about a new gateway IP address as an example)
typo fixes (includes whitespace fixes)
changes which only affect machines maintained by the requester themselves
changes which nobody reviewed / which did not receive any input for more than one week