misc: include status code in message logged on theme retrieval errors (#20194)

hobo/context_processors.py

@@ -86,7 +86,7 @@ class RemoteTemplate(object):
     def update_content(self, in_thread=True):
         r = requests.get(settings.THEME_SKELETON_URL, params={'source': self.source})
         if r.status_code != 200:
-            logger.error('failed to retrieve theme')
+            logger.error('failed to retrieve theme (status code: %s)', r.status_code)
             return None
         self.cache(r.text)
         if r.headers.get('X-Combo-Skeleton-Pages'):