monitoring: Rename core-application to repo-management and refactor

Created by: indradhanush

Stacked PR on top of #26865 which is a pre-requisite.

Also, when this is rolled out, we will need to rename the team in OpsGenie to repo-management.

In this commit we introduce a struct to store the owner name, team name and the slug since now all the teams have a custom format. As a result, the existing switch-case in toMarkdown can be replaced in exchange of a better data struct-ure (pun intended).

Test Plan

Test if alerts are being triggered post merge.