deps(ci): update actions/setup-node action to v7 (#1199)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [actions/setup-node](https://redirect.github.com/actions/setup-node) |
action | major | `v6` → `v7` |

---

### Release Notes

<details>
<summary>actions/setup-node (actions/setup-node)</summary>

###
[`v7.0.0`](https://redirect.github.com/actions/setup-node/compare/v6.5.0...v7.0.0)

[Compare
Source](https://redirect.github.com/actions/setup-node/compare/v7.0.0...v7.0.0)

###
[`v7`](https://redirect.github.com/actions/setup-node/compare/v6.5.0...v7.0.0)

[Compare
Source](https://redirect.github.com/actions/setup-node/compare/v6.5.0...v7.0.0)

</details>

---

### Configuration

📅 **Schedule**: (in timezone Europe/Zurich)

- Branch creation
  - "after 9pm,before 6am"
- Automerge
  - At any time (no schedule defined)

🚦 **Automerge**: Enabled.

♻ **Rebasing**: Whenever PR is behind base branch, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

This PR was generated by [Mend Renovate](https://mend.io/renovate/).
View the [repository job
log](https://developer.mend.io/github/dotnet/dotnet-operator-sdk).

<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0My4yNTkuMiIsInVwZGF0ZWRJblZlciI6IjQzLjI1OS4yIiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6WyJkZXBlbmRlbmNpZXMiXX0=-->

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

Author: renovate[bot]

.github/workflows/docs-test.yml

@@ -17,7 +17,7 @@ jobs:
       - uses: actions/checkout@v7
 
       - name: Setup Node.js
-        uses: actions/setup-node@v6
+        uses: actions/setup-node@v7
         with:
           node-version: "24"
           cache: "npm"

.github/workflows/dotnet-pre-release.yml

@@ -34,7 +34,7 @@ jobs:
           user: ${{ secrets.NUGET_USER }}
 
       - name: Setup Node
-        uses: actions/setup-node@v6
+        uses: actions/setup-node@v7
         with:
           node-version: 24
           cache: npm

.github/workflows/dotnet-release.yml

@@ -33,7 +33,7 @@ jobs:
           user: ${{ secrets.NUGET_USER }}
 
       - name: Setup Node
-        uses: actions/setup-node@v6
+        uses: actions/setup-node@v7
         with:
           node-version: 24
           cache: npm

.github/workflows/gh-pages.yml

@@ -26,7 +26,7 @@ jobs:
       - uses: actions/checkout@v7
 
       - name: Setup Node.js
-        uses: actions/setup-node@v6
+        uses: actions/setup-node@v7
         with:
           node-version: "24"
           cache: "npm"