Canonical Code Coverage Teams and CODEOWNERS Assignment

WIP - Dumping ground for ideas (stolen from Brian S) :)

Goals

High Level

• Build Code Owners file per ci run
• Assign code coverage teams upon code coverage ingestion
  • Remove the teams assignment pipeline http put
    • This removes the need to to deal with the formatting issue of the painless script

Impl Details

How it works now

Currently, the coverage ingestion process uploads an "inlined" version of the team assignment painless script, via the ES Client.