Sync blocks after loan migration

A huge percentage of the time, the loan migration process ends with a lot of spurious blocks that must be cleared via a call to /automated-patron-blocks/synchronization/job

This happens often enough that seems worthwhile to just automatically launch this after a loans migration process

Start by locating the loan migration completion path in the Python module or CLI and the existing use of /automated-patron-blocks/synchronization/job. Trace how migration completion is detected and identify the relevant tests or runnable migration flow. Done means the synchronization job is launched automatically after a loans migration and the spurious blocks no longer require a separate call.

Written by the indexing model from the issue text.