Fix qbittorrent upgrade strategy

test/qbittorent/upgrade_strategy

@@ -1,13 +1,17 @@
 #!/usr/bin/python3
 import json
+import re
 import sys
 
 from catalog_update.upgrade_strategy import semantic_versioning
 
 
+RE_STABLE_VERSION = re.compile(r'[0-9]\.[0-9]\.[0-9]')
+
+
 def newer_mapping(image_tags):
     key = list(image_tags.keys())[0]
-    tags = {t: t for t in image_tags[key]}
+    tags = {t: t for t in image_tags[key] if RE_STABLE_VERSION.fullmatch(t)}
     version = semantic_versioning(list(tags))
     if not version:
         return {}