gh-120417: Modify test_bdb to use the import (#120628)

Run test_module_for_bdb with a specific namespace.

Author: vstinner

Lib/test/test_bdb.py

@@ -1046,8 +1046,9 @@ def main():
                 ('return', 1, '<module>'), ('quit', ),
             ]
             import test_module_for_bdb
+            ns = {'test_module_for_bdb': test_module_for_bdb}
             with TracerRun(self) as tracer:
-                tracer.runeval('test_module_for_bdb.main()', globals(), locals())
+                tracer.runeval('test_module_for_bdb.main()', ns, ns)
 
 class IssuesTestCase(BaseTestCase):
     """Test fixed bdb issues."""