bump actions/setup-node from 6 to 7 (#539)

Bumps [actions/setup-node](https://github.com/actions/setup-node) from 6 to 7.
- [Release notes](https://github.com/actions/setup-node/releases)
- [Commits](https://github.com/actions/setup-node/compare/v6...v7)

---
updated-dependencies:
- dependency-name: actions/setup-node
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/agent-image-smoke.yml

@@ -129,7 +129,7 @@ jobs:
           done
 
       - name: Set up Node (for the panel screenshot step below)
-        uses: actions/setup-node@v6
+        uses: actions/setup-node@v7
         with:
           node-version: '22'
 

.github/workflows/panel-ci.yml

@@ -58,7 +58,7 @@ jobs:
           fetch-tags: true
 
       - name: Set up Node
-        uses: actions/setup-node@v6
+        uses: actions/setup-node@v7
         with:
           # pnpm 11 (pinned in panel/package.json via packageManager) requires
           # Node >=22.13; Node 20 makes `pnpm install` fail the engines check.