Merge pull request #8058 from ampproject/dependabot/npm_and_yarn/postcss-8.5.5

Bump postcss from 8.5.4 to 8.5.5

Author: swissspidy

package-lock.json

@@ -89,7 +89,7 @@
     "lodash": "4.17.21",
     "moment": "2.30.1",
     "npm-run-all": "4.1.5",
-    "postcss": "8.5.4",
+    "postcss": "8.5.5",
     "postcss-import": "16.1.0",
     "postcss-nested": "7.0.2",
     "postcss-preset-env": "10.1.6",