Deprecate DeviceState.no_save

meshtastic/deviceonly.proto

@@ -54,8 +54,9 @@ message DeviceState {
   /*
    * Used only during development.
    * Indicates developer is testing and changes should never be saved to flash.
+   * Deprecated in 2.3.1
    */
-  bool no_save = 9;
+  bool no_save = 9 [deprecated = true];
 
   /*
    * Some GPS receivers seem to have bogus settings from the factory, so we always do one factory reset.