merge gatekeepr failed on push event (merge pr)

[alon-dotan-starkware]

Looks like there is some missing env var nor param when action triggered by push event
Im getting the following error

Error: failed to create validator: reference of repository is empty
Usage:
  merge-gatekeeper validate [flags]

Flags:
  -h, --help             help for validate
  -i, --ignored string   set ignored jobs (comma-separated list)
      --interval uint    set validate interval second (default [10](https://github.com/starkware-libs/sequencer/actions/runs/10330954989/job/28600586832#step:3:11))
      --ref string       set ref of github repository. the ref can be a SHA, a branch name, or tag name
  -r, --repo string      set github repository
  -s, --self string      set self job name (default "merge-gatekeeper")
      --timeout uint     set validate timeout second (default 600)

Global Flags:
  -t, --token string   set github token

failed to execute command: failed to create validator: reference of repository is empty

action config:

on:
  push:
    branches:
      - main
      - main-v[0-9].**
    tags:
      - v[0-9].**

  pull_request:
    types:
      - opened
      - reopened
      - synchronize
      - auto_merge_enabled
      - edited
      
  ....
  jobs:
    ....
    ....
    merge-gatekeeper:
    runs-on: ubuntu-latest
    # Restrict permissions of the GITHUB_TOKEN.
    # Docs: https://docs.github.com/en/actions/using-jobs/assigning-permissions-to-jobs
    permissions:
      checks: read
      statuses: read
    steps:
      - name: Run Merge Gatekeeper
        if: github.event_name != 'merge_group'
        uses: upsidr/merge-gatekeeper@v1
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          timeout: 1200
          ignored: "code-review/reviewable"

      - name: Run Merge Gatekeeper in Merge Queue
        if: github.event_name == 'merge_group'
        uses: upsidr/merge-gatekeeper@v1
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          ref: ${{github.ref}}
          timeout: 1200
          ignored: "code-review/reviewable"