Revert "chore(website): switch to modern yarn" (#1052)

Reverts #1048
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Seems that broke the build.

Author: Saadnajmi

website/.yarn/install-state.gz

@@ -15,6 +15,5 @@
   },
   "dependencies": {
     "docusaurus-init": "^1.14.1"
-  },
-  "packageManager": "yarn@4.9.2"
+  }
 }