fix packaging and imports and introduce tests with pytest.

still issues with celery worker.

application/parser/file/html_parser.py

@@ -7,7 +7,7 @@ import re
 from pathlib import Path
 from typing import Dict, Union
 
-from parser.file.base_parser import BaseParser
+from application.parser.file.base_parser import BaseParser
 
 
 class HTMLParser(BaseParser):