Bump postcss-loader from 5.1.0 to 5.2.0 (#568)

Bumps [postcss-loader](https://github.com/webpack-contrib/postcss-loader) from 5.1.0 to 5.2.0.
- [Release notes](https://github.com/webpack-contrib/postcss-loader/releases)
- [Changelog](https://github.com/webpack-contrib/postcss-loader/blob/master/CHANGELOG.md)
- [Commits](webpack-contrib/postcss-loader@v5.1.0...v5.2.0)

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Author: dependabot[bot]

package.json

@@ -24,7 +24,7 @@
     "fibers": "5.0.0",
     "mini-css-extract-plugin": "1.3.9",
     "postcss": "8.2.8",
-    "postcss-loader": "5.1.0",
+    "postcss-loader": "5.2.0",
     "sass": "1.32.8",
     "sass-loader": "11.0.1",
     "stylelint": "13.12.0",