Script downstream check correlation (#1566)

Adding a script that helps correlating
https://github.com/pulumi/pulumi-terraform-bridge/blob/master/.github/workflows/update-providers-test.yml
results. Forgive the Python and lack of integration into GitHub actions
but hoping it will prove useful as-is to make it easy to find failing
PRs and close succeeding ones. Courtesy @blampe for the logic.

scripts/downstream_checks.py

@@ -0,0 +1,47 @@
+import argparse
+import json
+import requests
+import subprocess as sp
+
+ap = argparse.ArgumentParser()
+ap.add_argument('--hash', required=True)
+args = ap.parse_args()
+c = args.hash
+
+query = """
+{
+  search(query: "is:open is:pr org:pulumi ???", type: ISSUE, first: 100) {
+    edges {
+      node {
+        ... on PullRequest {
+          number
+          url
+          mergeable
+          title
+          commits(last: 1) { nodes { commit { statusCheckRollup { state } } } }
+        }
+      }
+    }
+  }
+}
+""".replace("???", c)
+
+
+token = sp.check_output(["gh", "auth", "token"]).decode('utf-8').strip()
+
+resp = requests.post('https://api.github.com/graphql',
+                     headers={'Authorization': f'bearer {token}'},
+                     json={"query": query})
+
+r = resp.json()
+
+for e in r['data']['search']['edges']:
+    if e.get('node', {}).get('title', '') != f'Upgrade pulumi-terraform-bridge to {c}':
+        continue
+
+    checks = e.get('node', {}).get('commits', {}).get('nodes', [{}])[0]['commit']['statusCheckRollup']['state']
+    if checks == 'SUCCESS':
+        url = e['node']['url']
+        sp.check_call(['gh', 'pr', 'close', url])
+    else:
+        print('FAILED', e['node']['url'])