build(deps-dev): bump gulp-sass from 5.1.0 to 6.0.0 in the gulp group

Bumps the gulp group with 1 update: [gulp-sass](https://github.com/dlmanning/gulp-sass).


Updates `gulp-sass` from 5.1.0 to 6.0.0
- [Release notes](https://github.com/dlmanning/gulp-sass/releases)
- [Changelog](https://github.com/dlmanning/gulp-sass/blob/master/CHANGELOG.md)
- [Commits](dlmanning/gulp-sass@v5.1.0...v6.0.0)

---
updated-dependencies:
- dependency-name: gulp-sass
  dependency-type: direct:development
  update-type: version-update:semver-major
  dependency-group: gulp
...

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

package.json

@@ -76,7 +76,7 @@
     "gulp-babel": "^8.0.0",
     "gulp-concat": "^2.6.1",
     "gulp-csso": "^4.0.1",
-    "gulp-sass": "^5.1.0",
+    "gulp-sass": "^6.0.0",
     "gulp-sourcemaps": "^3.0.0",
     "gulp-svgmin": "^4.1.0",
     "gulp-terser": "^2.1.0",