Steal the rerun flaky tests script

From https://github.com/tgstation/tgstation/blob/4f41277de989e573af881566620fc87edd7394d9

.github/workflows/rerunFlakyTests.yml

@@ -0,0 +1,20 @@
+name: Rerun Flaky Live Tests
+on:
+  workflow_run:
+    workflows: [CI Pipeline]
+    types:
+    - completed
+jobs:
+  rerun_flaky_tests:
+    runs-on: ubuntu-latest
+    if: ${{ github.event.workflow_run.conclusion == 'failure' && github.event.workflow_run.run_attempt == 1 }}
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v4
+
+    - name: Rerun flaky tests
+      uses: actions/github-script@v6
+      with:
+        script: |
+          const { rerunFlakyTests } = await import('${{ github.workspace }}/.github/workflows/scripts/rerunFlakyTests.js')
+          await rerunFlakyTests({ github, context })

.github/workflows/scripts/rerunFlakyTests.js

@@ -0,0 +1,49 @@
+// Only check jobs that start with these.
+// Helps make sure we don't restart something like which is not known to be flaky.
+const CONSIDERED_JOBS = [
+	"Windows Live Tests",
+	"Linux Live Tests",
+];
+
+async function getFailedJobsForRun(github, context, workflowRunId, runAttempt) {
+	const {
+		data: { jobs },
+	} = await github.rest.actions.listJobsForWorkflowRunAttempt({
+		owner: context.repo.owner,
+		repo: context.repo.repo,
+		run_id: workflowRunId,
+		attempt_number: runAttempt,
+	});
+
+	return jobs
+		.filter((job) => job.conclusion === "failure")
+		.filter((job) =>
+			CONSIDERED_JOBS.some((title) => job.name.startsWith(title))
+		);
+}
+
+export async function rerunFlakyTests({ github, context }) {
+	const failingJobs = await getFailedJobsForRun(
+		github,
+		context,
+		context.payload.workflow_run.id,
+		context.payload.workflow_run.run_attempt
+	);
+
+	if (failingJobs.length > 1) {
+		console.log("Multiple jobs failing. PROBABLY not flaky, not rerunning.");
+		return;
+	}
+
+	if (failingJobs.length === 0) {
+		throw new Error(
+			"rerunFlakyTests should not have run on a run with no failing jobs"
+		);
+	}
+
+	github.rest.actions.reRunWorkflowFailedJobs({
+		owner: context.repo.owner,
+		repo: context.repo.repo,
+		run_id: context.payload.workflow_run.id,
+	});
+}