Investigate if single column FK indexes are still needed after partitioning ci_builds

Everyone can contribute. Help move this issue forward while earning points, leveling up and collecting rewards.

• Close this issue

For partitioning ci_builds we need to add composite Foreign Keys and indexes for them, but we still have indexes for the single column FKs that might not be needed.

List of indexes that need to be investigated:

old index name	potential new candidate
index_ci_builds_runner_session_on_build_id	index_ci_builds_runner_session_on_partition_id_build_id