Bump sass from 1.49.9 to 1.77.8 in /ntbs-service

Bumps [sass](https://github.com/sass/dart-sass) from 1.49.9 to 1.77.8.
- [Release notes](https://github.com/sass/dart-sass/releases)
- [Changelog](https://github.com/sass/dart-sass/blob/main/CHANGELOG.md)
- [Commits](sass/dart-sass@1.49.9...1.77.8)

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

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

ntbs-service/package.json

@@ -28,7 +28,7 @@
  "govuk-frontend": "4.0.1",
  "nhsuk-frontend": "6.1.0",
  "qs": "6.10.3",
- "sass": "1.49.9",
+ "sass": "1.77.8",
  "url-loader": "4.1.1",
  "vue": "^2.7.14",
  "vue-accessible-modal": "0.4.0"