fix warning

src/ansible-webui/aw/config/main.py

@@ -1,6 +1,7 @@
 from os import environ
 from importlib.metadata import version, PackageNotFoundError
 from sys import stderr
+from warnings import warn
 
 from pytz import all_timezones, timezone
 
@@ -35,7 +36,7 @@ def init_globals():
     environ['PYTHONUNBUFFERED'] = '1'
 
     if 'AW_SECRET' not in environ:
-        raise UserWarning(
+        warn(
             "The environmental variable 'AW_SECRET' was not supplied! "
             "Job-secrets like passwords might not be loadable after restart."
         )