Bump @angular/forms from 20.3.2 to 21.2.11 in /angular-app

Bumps [@angular/forms](https://github.com/angular/angular/tree/HEAD/packages/forms) from 20.3.2 to 21.2.11.
- [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/v21.2.11/packages/forms)

---
updated-dependencies:
- dependency-name: "@angular/forms"
  dependency-version: 21.2.9
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

angular-app/package-lock.json

@@ -16,7 +16,7 @@
     "@angular/common": "20.3.2",
     "@angular/compiler": "20.3.2",
     "@angular/core": "20.3.2",
-    "@angular/forms": "20.3.2",
+    "@angular/forms": "21.2.11",
     "@angular/localize": "20.3.2",
     "@angular/material": "20.0.5",
     "@angular/platform-browser-dynamic": "20.3.2",