Bump @angular/platform-browser in /web_embedding/ng-flutter

Bumps [@angular/platform-browser](https://github.com/angular/angular/tree/HEAD/packages/platform-browser) from 18.2.13 to 19.0.3.
- [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/19.0.3/packages/platform-browser)

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

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

web_embedding/ng-flutter/package.json

@@ -18,7 +18,7 @@
     "@angular/core": "^19.0.3",
     "@angular/forms": "^19.0.1",
     "@angular/material": "^19.0.2",
-    "@angular/platform-browser": "^18.0.1",
+    "@angular/platform-browser": "^19.0.3",
     "@angular/platform-browser-dynamic": "^19.0.0",
     "@angular/router": "^19.0.1",
     "rxjs": "~7.8.1",