Ensure we exit as soon as possible when signal is received

main.py

@@ -271,7 +271,7 @@ def main():
     libreview_session = LibreViewSession()
     libreview_session.authenticate(config['CREDENTIALS']['EMAIL'], config['CREDENTIALS']['PASSWORD'])
 
-    if libreview_session.authenticated:
+    if libreview_session.authenticated and not SHOULD_EXIT:
         logging.info("successfully authenticated with LibreView")
     else:
         logging.fatal("failed to authenticate with LibreView")