chore: output.file is already set in config; CLI arg is redundant

Author: haoqunjiang

package.json

@@ -19,7 +19,7 @@
   "scripts": {
     "prepare": "husky",
     "format": "prettier --write .",
-    "build": "rolldown -c rolldown.config.ts --file bundle.js",
+    "build": "rolldown -c rolldown.config.ts",
     "snapshot": "zx ./scripts/snapshot.mjs",
     "pretest": "pnpm run build && pnpm run snapshot",
     "test": "zx ./scripts/test.mjs",