chore(deps): update pnpm/action-setup action to v6 (#5521)

Co-authored-by: homarr-renovate[bot] <158783068+homarr-renovate[bot]@users.noreply.github.com>

tooling/github/setup/action.yml

@@ -4,7 +4,7 @@ description: "Common setup steps for Actions"
 runs:
   using: composite
   steps:
-    - uses: pnpm/action-setup@v5
+    - uses: pnpm/action-setup@v6
     - uses: actions/setup-node@v6
       with:
         node-version: 24.14.1