Bump actions/github-script from 6 to 7 (#323)

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

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

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

Author: dependabot[bot]

.github/workflows/nightly.yml

@@ -38,7 +38,7 @@ jobs:
           repository: TileDB-Inc/TileDB
           ref: ${{ matrix.tag }}
       - name: Export GitHub Actions cache variables
-        uses: actions/github-script@v6
+        uses: actions/github-script@v7
         with:
           script: |
             core.exportVariable('ACTIONS_CACHE_URL', process.env.ACTIONS_CACHE_URL || '');