Merge pull request #938 from openwebwork/dependabot/npm_and_yarn/htdocs/postcss-8.4.31

Bump postcss from 8.4.21 to 8.4.31 in /htdocs

Author: drgrice1

htdocs/package-lock.json

@@ -23,7 +23,7 @@
         "autoprefixer": "^10.4.13",
         "chokidar": "^3.5.3",
         "cssnano": "^6.0.0",
-        "postcss": "^8.4.21",
+        "postcss": "^8.4.31",
         "rtlcss": "^4.0.0",
         "sass": "^1.57.1",
         "terser": "^5.16.1",