Update actions/setup-node action to v6 (#177)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/push.yml

@@ -56,7 +56,7 @@ jobs:
           go-version: 1.24.x
 
       - name: Setup Node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version: 22.x
 

.github/workflows/release.yml

@@ -110,7 +110,7 @@ jobs:
         uses: pulumi/action-install-pulumi-cli@v2.0.0
 
       - name: Setup Node
-        uses: actions/setup-node@v5
+        uses: actions/setup-node@v6
         with:
           node-version: ${{matrix.nodeversion}}
           registry-url: ${{env.NPM_REGISTRY_URL}}