chore(deps): pin devdependency rollup to 4.21.1

Author: renovate[bot]

package.json

@@ -41,7 +41,7 @@
     "bumpp": "latest",
     "eslint": "latest",
     "lint-staged": "latest",
-    "rollup": "^4.21.1",
+    "rollup": "4.21.1",
     "simple-git-hooks": "latest",
     "typescript": "latest",
     "unbuild": "latest",