Show warning if assignee is trying to merge a PR without reviews

Expected Behavior

PR shouldn't be merged when PR has no reviews or if assignee is trying to merge it.

Actual Behavior

PR was getting merged

Steps to Reproduce the Problem

1. We have below configuration in mergify.yaml

  ---
pull_request_rules:
  - name: automatic merge
    conditions:
      - label!=DNM
      - label!=work-in-progress
      - base=master
      - "approved-reviews-by=@red-hat-storage/cephci-top-level-reviewers"
      - "check-success=tox (3.9.18)"
      - check-success=WIP
    actions:
      merge:
        method: merge
  - name: ask to resolve conflict
    conditions:
      - conflict
    actions:
      comment:
        message: >
          "This pull request now has conflicts with the target branch.
          Could you please resolve conflicts and force push the corrected
          changes?"

2. So anyone can have a label approved in labels, so its getting merged.
3. Can we have a condition in above configuration file in such a way only when reviewers keep label as approved, PR should get merged.

Specifications

• Pull Request URL:
• Mergify Config URL:

Start with the mergify.yaml example and trace how approved-reviews-by, labels, assignees, and merge actions are evaluated. Reproduce the case where an approved label permits merging without a qualifying review, then verify that the configured policy distinguishes reviewer approval and assignee attempts before merging.