chore(deps-dev): bump postcss from 8.2.4 to 8.2.8 (#72)

Bumps [postcss](https://github.com/postcss/postcss) from 8.2.4 to 8.2.8.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.2.4...8.2.8)

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -26,7 +26,7 @@
     "@fullhuman/postcss-purgecss": "^4.0.2",
     "@tailwindcss/typography": "^0.4.0",
     "autoprefixer": "^10.2.5",
-    "postcss": "^8.2.4",
+    "postcss": "^8.2.8",
     "postcss-cli": "^8.3.1",
     "postcss-import": "^14.0.0",
     "prettier": "^2.2.1",