Bump @angular/animations in /web_embedding/ng-flutter

Bumps [@angular/animations](https://github.com/angular/angular/tree/HEAD/packages/animations) from 20.3.16 to 21.1.1.
- [Release notes](https://github.com/angular/angular/releases)
- [Changelog](https://github.com/angular/angular/blob/main/CHANGELOG.md)
- [Commits](https://github.com/angular/angular/commits/v21.1.1/packages/animations)

---
updated-dependencies:
- dependency-name: "@angular/animations"
  dependency-version: 21.1.1
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

web_embedding/ng-flutter/package.json

@@ -11,7 +11,7 @@
   },
   "private": true,
   "dependencies": {
-    "@angular/animations": "^20.0.3",
+    "@angular/animations": "^21.1.1",
     "@angular/cdk": "^20.1.0",
     "@angular/common": "^20.1.4",
     "@angular/compiler": "^21.1.0",