Bump stylus-loader from 3.0.2 to 6.2.0 in /template

Bumps [stylus-loader](https://github.com/webpack-contrib/stylus-loader) from 3.0.2 to 6.2.0.
- [Release notes](https://github.com/webpack-contrib/stylus-loader/releases)
- [Changelog](https://github.com/webpack-contrib/stylus-loader/blob/master/CHANGELOG.md)
- [Commits](webpack/stylus-loader@v3.0.2...v6.2.0)

---
updated-dependencies:
- dependency-name: stylus-loader
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

template/package.json

@@ -29,7 +29,7 @@
     "node-sass": "^6.0.1",
     "sass-loader": "10.2.0",
     "stylus": "0.54.8",
-    "stylus-loader": "3.0.2",
+    "stylus-loader": "6.2.0",
     "electron-devtools-installer": "^3.2.0",
     "vuetify": "^2.5.10",
     "webpack": "^4.46.0",