Replace responses library HTTP mocking with direct feedparser.parse()
mocking to eliminate XML parsing compatibility issues. All integration
tests now mock feedparser output directly, avoiding HTTP layer complexity.
Changes:
- Replace responses.activate decorators with feedparser.parse patches
- Mock feed objects directly instead of mocking HTTP responses
- Remove responses library dependency from requirements-test.txt
- Simplify test setup by eliminating XML string encoding issues
This approach provides more reliable testing by directly controlling
feedparser behavior rather than relying on HTTP mocking layer.
