Remove return value from load_config, so no illusion of purity.

This method already relies on object state anyway and writes back
to self.config, so the return value is unnecessary.

etiquette/photodb.py

@@ -1313,7 +1313,7 @@ class PhotoDB(
 
         # CONFIG
         self.config_filepath = self.data_directory.with_child(constants.DEFAULT_CONFIGNAME)
-        self.config = self.load_config()
+        self.load_config()
         self.log.setLevel(self.config['log_level'])
 
         # OTHER
@@ -1542,8 +1542,6 @@ class PhotoDB(
         if needs_dump:
             self.save_config()
 
-        return config
-
     def save_config(self):
         with open(self.config_filepath.absolute_path, 'w', encoding='utf-8') as handle:
             handle.write(json.dumps(self.config, indent=4, sort_keys=True))