Update garak/configurable.py

I find additional documentation to rarely be a bad thing, however if you disagree then we can remove it

Co-authored-by: Jeffrey Martin <jmartin@Op3n4M3.dev>
Signed-off-by: au70ma70n <168219140+au70ma70n@users.noreply.github.com>

garak/configurable.py

@@ -58,7 +58,6 @@ def _load_config(self, config_root=_config):
             if not hasattr(self, "key_env_var"):
                 self.key_env_var = self.ENV_VAR
         self._validate_env_var()
-        # mark as configured, do not change as this is a one-time operation that should not be called again
         self._instance_configured = True
 
     def _apply_config(self, config):