Extend codeowner sections to assign multiple paths to a single group of users
### Issue
The exact same codeowner section name can show up multiple times in the MR approval widget. This is confusing and limits how we can extend the functionality of codeowners/approval rules in other areas
### Proposal
Add ability to group many paths under the same `section name + users`. An example of how I might expect this to be configured
1. First line- section name
2. Second line- Users
3. Next lines - All paths
In the MR, this should result in a single `Frontend` codeowner rule being displayed, with all members of the frontend maintainer group listed (example below)
| Current codeowner file configuration | Proposal |
| ------ | ------ |
|  |  |
issue