Bump sass from 1.77.8 to 1.78.0 (#343)

Bumps [sass](https://github.com/sass/dart-sass) from 1.77.8 to 1.78.0.
- [Release notes](https://github.com/sass/dart-sass/releases)
- [Changelog](https://github.com/sass/dart-sass/blob/main/CHANGELOG.md)
- [Commits](sass/dart-sass@1.77.8...1.78.0)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -35,7 +35,7 @@
     "nhsuk-frontend": "^8.3.0",
     "nunjucks": "^3.2.4",
     "path": "^0.12.7",
-    "sass": "^1.77.8"
+    "sass": "^1.78.0"
   },
   "devDependencies": {
     "eslint": "^8.56.0",