Add script and GitHub action to close orphaned PRs

This script automatically detects "orphaned" PRs in this repo, by
looking at the source PR, and if it is closed, will close the
cross-repo-test PR.

Additionally this adds a GitHub action to run it every Sunday.

Author: Fryguy

.github/workflows/close_prs.yaml

@@ -0,0 +1,22 @@
+---
+name: Close PRs
+
+on:
+  schedule:
+  - cron: "0 0 * * 0"
+  workflow_dispatch:
+
+jobs:
+  close-prs:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: "ruby"
+      timeout-minutes: 30
+    - name: Close PRs
+      env:
+        GITHUB_API_TOKEN: "${{ secrets.PR_TOKEN }}"
+      run: bin/close_prs

bin/close_prs

@@ -0,0 +1,58 @@
+#!/usr/bin/env ruby
+
+require "bundler/inline"
+gemfile do
+  source "https://rubygems.org"
+  gem "colorize"
+  gem "octokit"
+  gem "optimist"
+end
+
+opts = Optimist.options do
+  opt :dry_run, "Execute without making changes", :default => false
+end
+
+def close_pull_request(repo, number, dry_run:, **_)
+  if dry_run
+    puts "** dry_run: github.close_pull_request(#{repo.inspect}, #{number.inspect})".light_black
+  else
+    github.close_pull_request(repo, number)
+  end
+end
+
+def delete_branch(repo, branch, dry_run:, **_)
+  if dry_run
+    puts "** dry_run: github.delete_branch(#{repo.inspect}, #{branch.inspect})".light_black
+  else
+    github.delete_branch(repo, branch)
+  end
+end
+
+def github
+  @github ||= Octokit::Client.new(
+    :access_token  => ENV.fetch("GITHUB_API_TOKEN"),
+    :auto_paginate => true
+  )
+end
+
+CRT_REPO = "ManageIQ/manageiq-cross_repo-tests".freeze
+
+github.pull_requests(CRT_REPO, :state => "open").each do |crt_pr|
+  target = crt_pr.title.split(" ").last
+  next unless target.match?(%r{^ManageIQ/[^#]+#\d+$})
+
+  repo, number = target.split("#")
+  pr = github.pull_request(repo, number)
+
+  crt_pr_slug = "#{CRT_REPO}##{crt_pr.number}"
+  pr_slug = "#{repo}##{number}"
+
+  if pr.state == "closed"
+    puts "Closing #{crt_pr_slug} since #{pr_slug} is closed"
+    close_pull_request(CRT_REPO, crt_pr.number, **opts)
+    puts "Deleting branch #{crt_pr.head.ref}"
+    delete_branch(CRT_REPO, crt_pr.head.ref, **opts)
+  else
+    puts "Skipping #{crt_pr_slug} since #{pr_slug} is open"
+  end
+end