chore(deps-dev): Bump sass in /build/frontend-legacy

Bumps [sass](https://github.com/sass/dart-sass) from 1.98.0 to 1.99.0.
- [Release notes](https://github.com/sass/dart-sass/releases)
- [Changelog](https://github.com/sass/dart-sass/blob/main/CHANGELOG.md)
- [Commits](sass/dart-sass@1.98.0...1.99.0)

---
updated-dependencies:
- dependency-name: sass
  dependency-version: 1.99.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

build/frontend-legacy/package-lock.json

@@ -129,7 +129,7 @@
     "patch-package": "^8.0.1",
     "raw-loader": "^4.0.2",
     "regextras": "^0.8.0",
-    "sass": "^1.98.0",
+    "sass": "^1.99.0",
     "typescript": "^5.9.2",
     "vite": "^7.3.1",
     "vitest": "^4.1.0",