upload-snapshot: fix discovery of the git-artifacts runs

When a `push` wants to trigger a new snapshot to be uploaded using
already-built Git artifacts (which is the case when Git for Windows'
"Rebase to <git-version>" PRs are "merged" by updating the `main` ref),
after verifying that there is a valid `tag-git` Check Run,
GitForWindowsHelper wants to find the associated `git-artifacts`
workflow runs.

They can be identified using the `tag-git` _workflow_ run, though, i.e.
the ID of the workflow as run in `git-for-windows-automation`, not the
mirrored _Check Run_ in `git-for-windows/git`.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

GitForWindowsHelper/cascading-runs.js

@@ -344,6 +344,10 @@ const handlePush = async (context, req) => {
     if (!match[2] === commit) throw new Error(`Unexpected revision ${match[2]} '${latest.output.summary}' of tag-git run: ${latest.html_url}`)
     const ver = match[1]
 
+    const match2 = latest.output.text.match(/^For details, see \[this run\]\(https:\/\/github.com\/([^/]+)\/([^/]+)\/actions\/runs\/(\d+)\)/)
+    if (!match2) throw new Error(`Unexpected summary '${latest.output.summary}' of tag-git run: ${latest.html_url}`)
+    const [, , , tagGitWorkflowRunId] = match2
+
     // There is already a `tag-git` workflow run; Is there already an `upload-snapshot` run?
     const latestUploadSnapshotRun = (await listCheckRunsForCommit(
         context,
@@ -381,7 +385,7 @@ const handlePush = async (context, req) => {
                 workflowName
             )
             const needle =
-                `Build Git ${ver} artifacts from commit ${commit} (tag-git run #${latest.id})`
+                `Build Git ${ver} artifacts from commit ${commit} (tag-git run #${tagGitWorkflowRunId})`
             const latest2 = runs
                 .filter(run => run.output.summary === needle)
                 .sort((a, b) => a.id - b.id)

__tests__/index.test.js

@@ -465,9 +465,10 @@ let mockListCheckRunsForCommit = jest.fn((_context, _token, _owner, _repo, rev,
             conclusion: 'success',
             status: 'completed',
             output: {
-                summary: 'Tag Git already-tagged @88811'
+                summary: 'Tag Git already-tagged @88811',
+                text: 'For details, see [this run](https://github.com/x/y/actions/runs/123).\nTagged already-tagged\nDone!.'
             },
-            id: 123
+            id: 123456789
         }]
         if (checkRunName.startsWith('git-artifacts')) {
             const id = {