log_filter: make force debug filter work for real (#46127)

src/authentic2/log_filters.py

@@ -52,5 +52,6 @@ class RequestContextFilter(logging.Filter):
 
 class ForceDebugFilter(logging.Filter):
     def filter(self, record):
-        record.level = logging.DEBUG
-        return True
+        record.levelno = logging.DEBUG
+        record.levelname = 'DEBUG'
+        return super().filter(record)