chore: fix dependabot automerge action

Author: smlx

.github/workflows/dependabot-automerge.yaml

@@ -21,7 +21,7 @@ jobs:
         github-token: "${{ secrets.GITHUB_TOKEN }}"
     - name: Auto-merge Dependabot PRs
       # don't auto-merge action updates to appease OpenSSF scorecard
-      if: ! contains(steps.metadata.outputs.package-ecosystem, 'github-actions')
+      if: ${{ ! contains(steps.metadata.outputs.package-ecosystem, 'github-actions') }}
       run: gh pr merge --auto --merge "$PR_URL"
       env:
         PR_URL: ${{github.event.pull_request.html_url}}