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