fix(deps): update dependency clean-css to v5.2.1

Author: renovate-bot

package.json

@@ -44,7 +44,7 @@
 		"@tailwindcss/forms": "0.3.3",
 		"@tailwindcss/typography": "0.4.1",
 		"autoprefixer": "10.2.6",
-		"clean-css": "5.1.2",
+		"clean-css": "5.2.1",
 		"clean-css-cli": "5.3.0",
 		"elasticlunr": "0.9.5",
 		"eleventy-plugin-embed-everything": "1.13.2",

yarn.lock

@@ -805,10 +805,10 @@ clean-css-cli@5.3.0:
     commander "7.x"
     glob "^7.1.6"
 
-clean-css@5.1.2:
-  version "5.1.2"
-  resolved "https://registry.yarnpkg.com/clean-css/-/clean-css-5.1.2.tgz#6ea0da7286b4ddc2469a1b776e2461a5007eed54"
-  integrity sha512-QcaGg9OuMo+0Ds933yLOY+gHPWbxhxqF0HDexmToPf8pczvmvZGYzd+QqWp9/mkucAOKViI+dSFOqoZIvXbeBw==
+clean-css@5.2.1:
+  version "5.2.1"
+  resolved "https://registry.yarnpkg.com/clean-css/-/clean-css-5.2.1.tgz#e5bdb1bee5f332c67e98cb6181251d4f88c0a6ab"
+  integrity sha512-ooQCa1/70oRfVdUUGjKpbHuxgMgm8BsDT5EBqBGvPxMoRoGXf4PNx5mMnkjzJ9Ptx4vvmDdha0QVh86QtYIk1g==
   dependencies:
     source-map "~0.6.0"