[server] fix SQLite patch to ensure TZDatetime are properly typed
NB: at this point, the TZ info is completely ignored. It will be
properly handled in later commits.
sync_schema_props_perms('cwuri')
helper = repo.system_source.dbhelper
cu = session.cnxset.cu
helper.set_null_allowed(cu, 'moved_entities', 'extid', 'VARCHAR(256)', False)
commit()