workflow: move to pnpm (#4766)

scripts/preinstall.js

@@ -0,0 +1,7 @@
+if (!/pnpm/.test(process.env.npm_execpath || '')) {
+  console.warn(
+    `\u001b[33mThis repository requires using pnpm as the package manager ` +
+      ` for scripts to work properly.\u001b[39m\n`
+  )
+  process.exit(1)
+}