Bump undici and @actions/github in /scripts (#3716)

* Bump undici and @actions/github in /scripts

Bumps [undici](https://github.com/nodejs/undici) to 6.23.0 and updates ancestor dependency [@actions/github](https://github.com/actions/toolkit/tree/HEAD/packages/github). These dependencies need to be updated together.


Updates `undici` from 5.29.0 to 6.23.0
- [Release notes](https://github.com/nodejs/undici/releases)
- [Commits](nodejs/undici@v5.29.0...v6.23.0)

Updates `@actions/github` from 6.0.0 to 9.0.0
- [Changelog](https://github.com/actions/toolkit/blob/main/packages/github/RELEASES.md)
- [Commits](https://github.com/actions/toolkit/commits/HEAD/packages/github)

---
updated-dependencies:
- dependency-name: undici
  dependency-version: 6.23.0
  dependency-type: indirect
- dependency-name: "@actions/github"
  dependency-version: 9.0.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

* Esnure node 20

---------

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

Author: dependabot[bot]

.github/workflows/main.yaml

@@ -18,6 +18,10 @@ jobs:
     steps:
       - name: Checkout repo
         uses: actions/checkout@v2
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
       - name: Install dependencies
         run: |
           cd scripts

.github/workflows/webplat-relnotes.yaml

@@ -21,6 +21,11 @@ jobs:
       - name: Checkout repo
         uses: actions/checkout@v2
 
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+
       - name: Install dependencies
         run: |
           cd scripts