Fix bug in check deep tests script (#4941)

### Description
- Fix the nightly build check so it fails if the last completed build
was a failure or timed out.

### How has this been tested?
- Read the code twice
- I will do a manual test once this is merged

<small>By submitting this pull request, I confirm that my contribution
is made under the terms of the [MIT
license](https://github.com/dafny-lang/dafny/blob/master/LICENSE.txt).</small>

.github/workflows/check-deep-tests-reusable.yml

@@ -1,6 +1,7 @@
 name: Check Deep Tests (Reusable Workflow)
 
 on:
+  workflow_dispatch:
   workflow_call:
 
 jobs:

.github/workflows/check-for-workflow-run.js

@@ -16,13 +16,18 @@ module.exports = async ({github, context, core, workflow_id, sha, ...config}) =>
   const runFilterDesc = sha ? `${workflow_id} on ${sha}` : workflow_id
   for (const run of result.data.workflow_runs) {
     if ((!sha || run.head_sha === sha)) {
-      if (run.conclusion === "success") {
-        // The SHA is fully tested, exit with success
-        console.log(`Last run of ${runFilterDesc} succeeded: ${run.html_url}`)
-        return
-      } else if (run.status === "failure" || run.status === "timed_out") {
-        core.setFailed(`Last run of ${runFilterDesc} did not succeed: ${run.html_url}`)
-        return
+      // The status property can be one of: “queued”, “in_progress”, or “completed”.
+      if (run.status === "completed") {
+        // The conclusion property can be one of:
+        // “success”, “failure”, “neutral”, “cancelled”, “skipped”, “timed_out”, or “action_required”.
+        if (run.conclusion === "success") {
+          // The SHA is fully tested, exit with success
+          console.log(`Last run of ${runFilterDesc} succeeded: ${run.html_url}`)
+          return
+        } else if (run.conclusion === "failure" || run.conclusion === "timed_out") {
+          core.setFailed(`Last run of ${runFilterDesc} did not succeed: ${run.html_url}`)
+          return
+        }
       }
     }
   }