Bump actions/github-script from 7 to 8

Bumps [actions/github-script](https://github.com/actions/github-script) from 7 to 8.
- [Release notes](https://github.com/actions/github-script/releases)
- [Commits](https://github.com/actions/github-script/compare/v7...v8)

---
updated-dependencies:
- dependency-name: actions/github-script
  dependency-version: '8'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/add-issue-header.yml

@@ -20,7 +20,7 @@ jobs:
       issues: write
     timeout-minutes: 5
     steps:
-      - uses: actions/github-script@v7
+      - uses: actions/github-script@v8
         with:
           # language=JavaScript
           script: |

.github/workflows/new-bugs-announce-notifier.yml

@@ -18,7 +18,7 @@ jobs:
           node-version: 20
       - run: npm install mailgun.js form-data
       - name: Send notification
-        uses: actions/github-script@v7
+        uses: actions/github-script@v8
         env:
           MAILGUN_API_KEY: ${{ secrets.MAILGUN_PYTHON_ORG_MAILGUN_KEY }}
         with: