[3.15] gh-149977: Fix extra output of -m test test_lazy_import, again (GH-150965) (#150975)

gh-149977: Fix extra output of `-m test test_lazy_import`, again (GH-150965)
(cherry picked from commit 9b4090c)

Co-authored-by: sobolevn <mail@sobolevn.me>

Author: miss-islington

Lib/test/test_lazy_import/__init__.py

@@ -447,11 +447,15 @@ def test_lazy_import_pkg(self):
 
     def test_lazy_submodule_stored_in_parent_dict(self):
         """Accessing a lazy submodule should store it in the parent's __dict__."""
-        import test.test_lazy_import.data.lazy_import_pkg
+        out = io.StringIO()
+
+        with contextlib.redirect_stdout(out):
+            import test.test_lazy_import.data.lazy_import_pkg
 
         pkg = sys.modules["test.test_lazy_import.data.pkg"]
         self.assertIn("bar", pkg.__dict__)
         self.assertIs(pkg.__dict__["bar"], sys.modules["test.test_lazy_import.data.pkg.bar"])
+        self.assertIn("BAR_MODULE_LOADED", out.getvalue())
 
     def test_lazy_import_pkg_cross_import(self):
         """Cross-imports within package should preserve lazy imports."""