Reset branch if the devel branch is based on Factory

This happens in packages that change their devel project over time. Then
the commit in the devel project no longer has the parent in the devel branch
but is based on factory

lib/obs.py

@@ -5,11 +5,10 @@ import time
 import urllib.parse
 import xml.etree.ElementTree as ET
 from urllib.error import HTTPError
-from pathlib import Path
-from lib.proxy_sha256 import md5
 
 import osc.core
 
+from lib.proxy_sha256 import md5
 from lib.request import Request
 from lib.user import User
 
@@ -164,7 +163,7 @@ class OBS:
         cachedir: str,
         file_md5: str,
     ) -> None:
-        
+
         cached_file = self._path_from_md5(name, cachedir, file_md5)
         if not self.in_cache(name, cachedir, file_md5):
             with (dirpath / name).open("wb") as f: