Update deploy.yml

Author: SimonB50

.github/workflows/deploy.yml

@@ -16,11 +16,15 @@ jobs:
       - uses: actions/setup-node@v4
         with:
           node-version: 18
+          cache: pnpm
+      - uses: pnpm/action-setup@v4
+        with:
+          version: 10
 
       - name: Install dependencies
-        run: npm ci
+        run: pnpm install --frozen-lockfile
       - name: Build website
-        run: npm run build
+        run: pnpm build
 
       - name: Upload Build Artifact
         uses: actions/upload-pages-artifact@v3