fix: resolve DeepSource issues in test files

- Use lazy % formatting in logging (PYL-W1203) in test_external_integrations.py
- Add @staticmethod to 3 methods not using self (PYL-R0201)
- Remove unused mock_media and mock_smtp variables (PYL-W0612)
- Remove redundant local reimports of upload_to_webdav (PYL-W0404)

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

tests/test_upload_webdav_comprehensive.py

@@ -532,14 +532,10 @@ class TestUploadToWebDAV:
 
     def test_module_importable(self):
         """Test that upload_to_webdav module is importable."""
-        from app.tasks.upload_to_webdav import upload_to_webdav
-
         assert callable(upload_to_webdav)
 
     def test_task_has_retry_configuration(self):
         """Test that the task has retry configuration from BaseTaskWithRetry."""
-        from app.tasks.upload_to_webdav import upload_to_webdav
-
         # BaseTaskWithRetry should provide retry configuration
         assert hasattr(upload_to_webdav, "max_retries")
         # BaseTaskWithRetry configures 3 retries