Add missing default for ConfigPreferences

src/invidious/helpers/helpers.cr

@@ -77,7 +77,7 @@ struct Config
   property statistics_enabled : Bool = false
   property admins : Array(String) = [] of String
   property external_port : Int32? = nil
-  property default_user_preferences : ConfigPreferences
+  property default_user_preferences : ConfigPreferences = ConfigPreferences.from_yaml("")
   property dmca_content : Array(String) = [] of String    # For compliance with DMCA, disables download widget using list of video IDs
   property check_tables : Bool = false                    # Check table integrity, automatically try to add any missing columns, create tables, etc.
   property cache_annotations : Bool = false               # Cache annotations requested from IA, will not cache empty annotations or annotations that only contain cards