zipline/.github/workflows/milestone.yml

name: 'Issue/PR Milestones'

on:
  pull_request:
    types: [opened, reopened]
  issues:
    types: [opened, reopened]

jobs:
  set:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: actions/github-script@v3
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            const milestone = 3
            if (context.eventName === 'issues') {
              github.issues.update({
                issue_number: context.issue.number,
                owner: context.repo.owner,
                repo: context.repo.repo,
                milestone
              })
            } else {
              github.pulls.update({
                pull_number: context.issue.number,
                owner: context.repo.owner,
                repo: context.repo.repo,
                milestone
              })
            }