User merge tool fails if source profile is georeferenced

Stack trace extract:

Updating feed entries...
Updating contributions versions and histories...
Unregistering from mailing lists...
Removing profile and user account...
Traceback (most recent call last):
File "/var/www/.build/venv/lib/python3.7/site-packages/sqlalchemy/engine/base. py", line 1277, in _execute_context
cursor, statement, parameters, context
File "/var/www/.build/venv/lib/python3.7/site-packages/sqlalchemy/engine/defau lt.py", line 608, in do_execute
cursor.execute(statement, parameters)
psycopg2.errors.ForeignKeyViolation: update or delete on table "documents" viola tes foreign key constraint "map_associations_document_id_fkey" on table "map_ass ociations"
DETAIL: Key (document_id)=(13274) is still referenced from table "map_associati ons".

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
File "c2corg_api/scripts/users/merge.py", line 275, in
main()
File "c2corg_api/scripts/users/merge.py", line 100, in main
merge_user_accounts(source_user_id, target_user_id, queue_config)
File "c2corg_api/scripts/users/merge.py", line 122, in merge_user_accounts
_remove_user_account(source_user_id)
File "c2corg_api/scripts/users/merge.py", line 270, in _remove_user_account
ArchiveUserProfile, None)
File "/var/www/c2corg_api/views/document_delete.py", line 340, in remove_whole _document
_remove_document(document_id)
File "/var/www/c2corg_api/views/document_delete.py", line 481, in _remove_docu ment
filter(Document.document_id == document_id). \
File "/var/www/.build/venv/lib/python3.7/site-packages/sqlalchemy/orm/query.py ", line 3926, in delete
delete_op.exec_()
File "/var/www/.build/venv/lib/python3.7/site-packages/sqlalchemy/orm/persiste nce.py", line 1697, in exec_
self._do_exec()
File "/var/www/.build/venv/lib/python3.7/site-packages/sqlalchemy/orm/persiste nce.py", line 1930, in _do_exec
self._execute_stmt(delete_stmt)
File "/var/www/.build/venv/lib/python3.7/site-packages/sqlalchemy/orm/persiste nce.py", line 1702, in _execute_stmt
self.result = self.query._execute_crud(stmt, self.mapper)
File "/var/www/.build/venv/lib/python3.7/site-packages/sqlalchemy/orm/query.py ", line 3568, in _execute_crud
return conn.execute(stmt, self._params)
sqlalchemy.exc.IntegrityError: (psycopg2.errors.ForeignKeyViolation) update or d elete on table "documents" violates foreign key constraint "map_associations_doc ument_id_fkey" on table "map_associations"
DETAIL: Key (document_id)=(13274) is still referenced from table "map_associati ons".

[SQL: DELETE FROM guidebook.documents WHERE guidebook.documents.document_id = %( document_id_1)s]
[parameters: {'document_id_1': 13274}]
(Background on this error at: http://sqlalche.me/e/13/gkpj)

Start in c2corg_api/scripts/users/merge.py, following merge_user_accounts into _remove_user_account, then inspect views/document_delete.py and the _remove_document path. Reproduce a merge with a georeferenced source profile and trace the map_associations foreign-key failure; done means the account merge completes without the documents deletion error.

Written by the indexing model from the issue text.