deploy: label versions with the commit subject only

A multi-line commit message made wrangler-action run each body line as a
separate command after a successful deploy, failing the run.

Author: rigor789

.github/workflows/deploy.yml

@@ -41,11 +41,15 @@ jobs:
       - run: npm test
       - run: npm run check
       - run: npx vite build
+      # The action runs every line of `command` as its own wrangler call, so
+      # only the commit subject may go into the message, and never a quote.
+      - id: commit
+        run: echo "subject=$(git log -1 --pretty=%s | tr -d '"')" >> "$GITHUB_OUTPUT"
       - uses: cloudflare/wrangler-action@v3
         with:
           apiToken: ${{ secrets.CLOUDFLARE_API_TOKEN }}
           accountId: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
           # Shown in the dashboard's version list: which commit, and which workflow run shipped it.
           command: >-
             deploy --tag "${{ github.sha }}"
-            --message "${{ github.workflow }} #${{ github.run_number }}: ${{ github.event.head_commit.message || github.ref_name }}"
+            --message "${{ github.workflow }} #${{ github.run_number }}: ${{ steps.commit.outputs.subject }}"