Better design to display many code owners in file view
### Problem to solve
With https://gitlab.com/gitlab-org/gitlab-ce/issues/53182 we are allowing groups to be code owners. This can more easily lead to a situation with hundreds or thousands of users listed as code owners in the file view. For example:
### Intended users
Developer
### Proposal
Perhaps the code owners list can be truncated after a certain number of users, with the possibility to collapse/expand. It should also be easier to read through the list, maybe using a stacked list, instead of inline.
### Links / references
issue