chore: add checkout step for ADC publishing

This tries to run a script from the source repo, so it should checkout
the source otherwise the script isn't going to be there 😭.

Author: rix0rrr

.github/workflows/release.yml

@@ -39,6 +39,7 @@ export class AdcPublishing extends Component {
       },
       if: '${{ needs.release.outputs.latest_commit == github.sha }}',
       steps: [
+        github.WorkflowSteps.checkout(),
         {
           uses: 'actions/setup-node@v4',
           with: {