Bump node-sass from 4.7.2 to 7.0.0

Bumps [node-sass](https://github.com/sass/node-sass) from 4.7.2 to 7.0.0.
- [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/v4.7.2...v7.0.0)

---
updated-dependencies:
- dependency-name: node-sass
  dependency-type: direct:development
...

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

package.json

@@ -32,7 +32,7 @@
     "karma-phantomjs-launcher": "^1.0.4",
     "karma-webpack": "^2.0.4",
     "loader-utils": "^1.1.0",
-    "node-sass": "^4.5.3",
+    "node-sass": "^7.0.0",
     "sass-loader": "^6.0.6",
     "style-loader": "^0.18.2",
     "url-loader": "^0.5.9",