build(deps-dev): Bump prettier from 1.18.2 to 1.19.1 in /frontend (#270)

Bumps [prettier](https://github.com/prettier/prettier) from 1.18.2 to 1.19.1.
- [Release notes](https://github.com/prettier/prettier/releases)
- [Changelog](https://github.com/prettier/prettier/blob/master/CHANGELOG.md)
- [Commits](prettier/prettier@1.18.2...1.19.1)

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

Author: dependabot-preview[bot]

frontend/package.json

@@ -41,7 +41,7 @@
     "mini-css-extract-plugin": "^0.8.0",
     "node-sass": "^4.12.0",
     "optimize-css-assets-webpack-plugin": "^5.0.3",
-    "prettier": "1.18.2",
+    "prettier": "1.19.1",
     "sass-loader": "^8.0.0",
     "standard": "^14.1.0",
     "terser-webpack-plugin": "^2.0.1",