chore(deps): update pnpm/action-setup action to v6

Author: renovate[bot]

.github/workflows/test.yaml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v6
-    - uses: pnpm/action-setup@v4
+    - uses: pnpm/action-setup@v6
     - name: Use Node.js 22
       uses: actions/setup-node@v4
       with: