Specify pnpm version in workflow file

Author: ryota-murakami

.github/workflows/malware-safe-chain.yml

@@ -13,6 +13,8 @@ jobs:
       - uses: actions/checkout@v4
       - name: Install pnpm
         uses: pnpm/action-setup@v4
+        with:
+          version: 10
       - name: Use Node.js
         uses: actions/setup-node@v4
         with: