Bump node-sass from 4.11.0 to 4.13.1

Bumps [node-sass](https://github.com/sass/node-sass) from 4.11.0 to 4.13.1.
- [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/v4.11.0...v4.13.1)

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

package.json

@@ -53,7 +53,7 @@
     "electron-builder": "20.38.4",
     "electron-webpack": "^2.6.2",
     "electron-webpack-ts": "^3.1.1",
-    "node-sass": "^4.11.0",
+    "node-sass": "^4.13.1",
     "nunjucks": "^3.2.0",
     "nunjucks-loader": "^3.0.0",
     "sass-loader": "^7.1.0",