Bump actions/github-script from 4.1.1 to 6 (sigstore#1497)

* Bump actions/github-script from 4.1.1 to 6

Bumps [actions/github-script](https://github.com/actions/github-script) from 4.1.1 to 6.
- [Release notes](https://github.com/actions/github-script/releases)
- [Commits](actions/github-script@deb7ae9...9ac0880)

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

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

* update version comment

Signed-off-by: Carlos Panato <ctadeu@gmail.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Carlos Panato <ctadeu@gmail.com>

.github/workflows/milestone.yaml

@@ -23,7 +23,7 @@ jobs:
       statuses: none
 
     steps:
-      - uses: actions/github-script@deb7ae927cc19ae3a8b57293dd5cd2f16171e1e2 # v4.1.1
+      - uses: actions/github-script@9ac08808f993958e9de277fe43a64532a609130e # v6.0.0
         with:
           script: |
             if (!context.payload.pull_request.merged) {