fix: update RSLIB_READY_MESSAGE to match latest rslib output

Author: Timeless0911

src/constant.ts

@@ -1,5 +1,5 @@
 export const PACKAGE_JSON = 'package.json';
 export const PLUGIN_LOG_TITLE = '[Rsbuild Workspace Dev Plugin]: ';
 
-export const RSLIB_READY_MESSAGE = 'build complete, watching for changes';
+export const RSLIB_READY_MESSAGE = 'watching for changes';
 export const TSUP_READY_MESSAGE = 'Watching for changes in';