Bump rollup from 4.19.1 to 4.21.1

Bumps [rollup](https://github.com/rollup/rollup) from 4.19.1 to 4.21.1.
- [Release notes](https://github.com/rollup/rollup/releases)
- [Changelog](https://github.com/rollup/rollup/blob/master/CHANGELOG.md)
- [Commits](rollup/rollup@v4.19.1...v4.21.1)

---
updated-dependencies:
- dependency-name: rollup
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -55,7 +55,7 @@
     "jest-fail-on-console": "^3.3.0",
     "npm-run-all2": "^6.2.2",
     "rimraf": "^6.0.1",
-    "rollup": "^4.19.1",
+    "rollup": "^4.21.1",
     "rollup-plugin-copy": "^3.5.0",
     "rollup-plugin-scss": "^4.0.0",
     "sass": "^1.77.8",