Bump node-sass from 5.0.0 to 6.0.0

Bumps [node-sass](https://github.com/sass/node-sass) from 5.0.0 to 6.0.0.
- [Release notes](https://github.com/sass/node-sass/releases)
- [Changelog](https://github.com/sass/node-sass/blob/master/CHANGELOG.md)
- [Commits](https://github.com/sass/node-sass/compare/v5.0.0...v6.0.0)

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

package.json

@@ -18,7 +18,7 @@
     "foreach-cli": "^1.8.1",
     "glob": "^7.1.4",
     "headr": "^0.0.4",
-    "node-sass": "^5.0.0",
+    "node-sass": "^6.0.0",
     "npm-run-all": "^4.1.5",
     "rollup": "^2.6.1",
     "rollup-plugin-babel": "^4.3.3",