Bump kentaro-m/auto-assign-action from 1.2.6 to 2.0.0

Bumps [kentaro-m/auto-assign-action](https://github.com/kentaro-m/auto-assign-action) from 1.2.6 to 2.0.0.
- [Release notes](https://github.com/kentaro-m/auto-assign-action/releases)
- [Commits](kentaro-m/auto-assign-action@v1.2.6...v2.0.0)

---
updated-dependencies:
- dependency-name: kentaro-m/auto-assign-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/auto_assignment.yaml

@@ -15,7 +15,7 @@ jobs:
     if: "!contains(github.event.pull_request.labels.*.name, 'Auto_Cherry_Picked')"
     runs-on: ubuntu-latest
     steps:
-      - uses: kentaro-m/auto-assign-action@v1.2.6
+      - uses: kentaro-m/auto-assign-action@v2.0.0
         with:
           repo-token: "${{ secrets.CHERRYPICK_PAT || github.token }}"
           configuration-path: ".github/auto_assign.yml"