Fix pipeline retry in a CI DAG

Previously a retried pipeline for builds in a DAG would cause the newly-created builds to sit in the created state because it would be waiting for the dependencies to trigger it. However, in the retry case, the dependencies may have already completed, so they will never trigger new builds.

We fix this by:

1. Looking up successful builds with the required names
2. Passing those build IDs to Ci::ProcessPipelineService to trigger builds with those dependencies.

Closes #36068 (closed)