install pnpm

Author: congmul

.github/workflows/azure-static-web-apps-ambitious-pond-0fe43071e.yml

@@ -19,6 +19,8 @@ jobs:
         with:
           submodules: true
           lfs: false
+      - name: Install PNPM
+        run: npm install -g pnpm    
       - name: Build And Deploy
         id: builddeploy
         uses: Azure/static-web-apps-deploy@v1