[3.12] gh-123780: Make test_pkgutil clean up spam module (GH-123036) (GH-123782)

(cherry picked from commit eca3fe4)

Co-authored-by: Malcolm Smith <[email protected]>

Author: miss-islington

Lib/test/test_pkgutil.py

@@ -624,8 +624,11 @@ def test_get_loader_handles_missing_spec_attribute(self):
         mod = type(sys)(name)
         del mod.__spec__
         with CleanImport(name):
-            sys.modules[name] = mod
-            loader = pkgutil.get_loader(name)
+            try:
+                sys.modules[name] = mod
+                loader = pkgutil.get_loader(name)
+            finally:
+                sys.modules.pop(name, None)
         self.assertIsNone(loader)
 
     @ignore_warnings(category=DeprecationWarning)
@@ -634,8 +637,11 @@ def test_get_loader_handles_spec_attribute_none(self):
         mod = type(sys)(name)
         mod.__spec__ = None
         with CleanImport(name):
-            sys.modules[name] = mod
-            loader = pkgutil.get_loader(name)
+            try:
+                sys.modules[name] = mod
+                loader = pkgutil.get_loader(name)
+            finally:
+                sys.modules.pop(name, None)
         self.assertIsNone(loader)
 
     @ignore_warnings(category=DeprecationWarning)