chore: bump postcss from 8.4.27 to 8.4.31 in /site (#10019)

Bumps [postcss](https://github.com/postcss/postcss) from 8.4.27 to 8.4.31.
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](https://github.com/postcss/postcss/compare/8.4.27...8.4.31)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: indirect
...

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

site/pnpm-lock.yaml

@@ -5917,7 +5917,7 @@ packages:
   /@types/node-fetch@2.6.6:
     resolution: {integrity: sha512-95X8guJYhfqiuVVhRFxVQcf4hW/2bCuoPwDasMf/531STFoNoWTT7YDnWdXHEZKqAGUigmpG31r2FE70LwnzJw==}
     dependencies:
-      '@types/node': 18.17.0
+      '@types/node': 18.18.1
       form-data: 4.0.0
     dev: true
 
@@ -5925,10 +5925,6 @@ packages:
     resolution: {integrity: sha512-Y1zz/LIuJek01+hlPNzzXQhmq/Z2BCP96j18MSXC0S0jSu/IG4FFxmBs7W4/lI2vPJ7foVfEB0hUVtnOjnCiTg==}
     dev: true
 
-  /@types/node@18.17.0:
-    resolution: {integrity: sha512-GXZxEtOxYGFchyUzxvKI14iff9KZ2DI+A6a37o6EQevtg6uO9t+aUZKcaC1Te5Ng1OnLM7K9NVVj+FbecD9cJg==}
-    dev: true
-
   /@types/node@18.18.1:
     resolution: {integrity: sha512-3G42sxmm0fF2+Vtb9TJQpnjmP+uKlWvFa8KoEGquh4gqRmoUG/N0ufuhikw6HEsdG2G2oIKhog1GCTfz9v5NdQ==}
 
@@ -11880,8 +11876,8 @@ packages:
       '@babel/runtime': 7.22.15
     dev: true
 
-  /postcss@8.4.27:
-    resolution: {integrity: sha512-gY/ACJtJPSmUFPDCHtX78+01fHa64FaU4zaaWfuh1MhGJISufJAH4cun6k/8fwsHYeK4UQmENQK+tRLCFJE8JQ==}
+  /postcss@8.4.31:
+    resolution: {integrity: sha512-PS08Iboia9mts/2ygV3eLpY5ghnUcfLV/EXTOW1E2qYxJKGGBUtNjN76FYHnMs36RmARn41bC0AZmn+rR0OVpQ==}
     engines: {node: ^10 || ^12 || >=14}
     dependencies:
       nanoid: 3.3.6
@@ -14218,7 +14214,7 @@ packages:
     dependencies:
       '@types/node': 18.18.1
       esbuild: 0.18.17
-      postcss: 8.4.27
+      postcss: 8.4.31
       rollup: 3.26.3
     optionalDependencies:
       fsevents: 2.3.3