Try to fix pnpm error on Dev Package Tests (#12774)

* Remove `-y` from `pnpm init`

* Change

tests/config/install-prettier.js

@@ -51,7 +51,11 @@ module.exports = (packageDir) => {
   fs.copyFileSync(file, packed);
   fs.unlinkSync(file);
 
-  execaSync(client, ["init", "-y"], { cwd: tmpDir });
+  if (client === "pnpm") {
+    execaSync(client, ["init"], { cwd: tmpDir });
+  } else {
+    execaSync(client, ["init", "-y"], { cwd: tmpDir });
+  }
 
   let installArguments = [];
   switch (client) {