build(deps-dev): bump css-loader from 3.3.2 to 3.4.0 in /webapp

Bumps [css-loader](https://github.com/webpack-contrib/css-loader) from 3.3.2 to 3.4.0.
- [Release notes](https://github.com/webpack-contrib/css-loader/releases)
- [Changelog](https://github.com/webpack-contrib/css-loader/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack-contrib/css-loader/compare/v3.3.2...v3.4.0)

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

webapp/package.json

@@ -115,7 +115,7 @@
     "babel-plugin-require-context-hook": "^1.0.0",
     "babel-preset-vue": "~2.0.2",
     "core-js": "~2.6.10",
-    "css-loader": "~3.3.2",
+    "css-loader": "~3.4.0",
     "eslint": "~6.7.2",
     "eslint-config-prettier": "~6.7.0",
     "eslint-config-standard": "~14.1.0",

webapp/yarn.lock

@@ -6166,10 +6166,10 @@ css-has-pseudo@^0.10.0:
     postcss "^7.0.6"
     postcss-selector-parser "^5.0.0-rc.4"
 
-css-loader@^3.0.0, css-loader@^3.2.0, css-loader@~3.3.2:
-  version "3.3.2"
-  resolved "https://registry.yarnpkg.com/css-loader/-/css-loader-3.3.2.tgz#41b2086528aa4fbf8c0692e874bc14f081129b21"
-  integrity sha512-4XSiURS+YEK2fQhmSaM1onnUm0VKWNf6WWBYjkp9YbSDGCBTVZ5XOM6Gkxo8tLgQlzkZOBJvk9trHlDk4gjEYg==
+css-loader@^3.0.0, css-loader@^3.2.0, css-loader@~3.4.0:
+  version "3.4.0"
+  resolved "https://registry.yarnpkg.com/css-loader/-/css-loader-3.4.0.tgz#9fb263436783117a41d014e45e8eaeba54dd6670"
+  integrity sha512-JornYo4RAXl1Mzt0lOSVPmArzAMV3rGY2VuwtaDc732WTWjdwTaeS19nCGWMcSCf305Q396lhhDAJEWWM0SgPQ==
   dependencies:
     camelcase "^5.3.1"
     cssesc "^3.0.0"