go/zodb/fs1: Fix Python database generator to work with recent zodbtools

As Zodbtools dropped ZODB3 support its run_with_zodb3py2_compat was
renamed to run_with_zodb4py2_compat:

nexedi/zodbtools@c59a54ca

go/zodb/storage/fs1/py/gen-testdata

 #!/usr/bin/env python2
 # -*- coding: utf-8 -*-
-# Copyright (C) 2017-2020  Nexedi SA and Contributors.
+# Copyright (C) 2017-2021  Nexedi SA and Contributors.
 #                          Kirill Smelkov <kirr@nexedi.com>
 #
 # This program is free software: you can Use, Study, Modify and Redistribute
@@ -23,7 +23,7 @@
 from ZODB.FileStorage import FileStorage
 from ZODB import DB
 from ZODB.Connection import TransactionMetaData
-from zodbtools.test.gen_testdata import gen_testdb, precommit, run_with_zodb3py2_compat
+from zodbtools.test.gen_testdata import gen_testdb, precommit, run_with_zodb4py2_compat
 from os import stat, remove
 from shutil import copyfile
 from golang.gcompat import qq
@@ -156,7 +156,7 @@ def main():
         vstor.store(vroot._p_oid, vroot._p_serial, '000 data 000', '', txn_stormeta)
         vstor.tpc_vote(txn_stormeta)
         # NO tpc_finish here so that status remain 'c' (voted) instead of ' ' (committed)
-    run_with_zodb3py2_compat(_)
+    run_with_zodb4py2_compat(_)
 
     st = stat(outfs)
     l  = st.st_size