MDEV-18713 Assertion `strcmp(share->unique_file_name,filename) || share->last_version' failed in test_if_reopen upon REPLACE into table with key on blob

close table->update_handler in close_thread_tables().
it's not enough to do it in sql_update.cc only, because
sql_insert.cc can also do updates (REPLACE) and even
sql_delete.cc can (DELETE ... FOR PORTION OF)