ci(action): bump ahmadnassri/action-dependabot-auto-merge

Bumps [ahmadnassri/action-dependabot-auto-merge](https://github.com/ahmadnassri/action-dependabot-auto-merge) from 2.4 to 2.6.
- [Release notes](https://github.com/ahmadnassri/action-dependabot-auto-merge/releases)
- [Commits](https://github.com/ahmadnassri/action-dependabot-auto-merge/compare/v2.4...v2.6)

---
updated-dependencies:
- dependency-name: ahmadnassri/action-dependabot-auto-merge
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

.github/workflows/auto-merge.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v2.4.0
-      - uses: ahmadnassri/action-dependabot-auto-merge@v2.4
+      - uses: ahmadnassri/action-dependabot-auto-merge@v2.6
         with:
           target: minor
           github-token: ${{ secrets.PAT }}