ci: quote a step name in package.yml that a bare colon had made unparseable

The public-readiness change replaced an em dash in a step name with a colon,
which turned the plain scalar into a mapping and made the whole file
unparseable. GitHub reported it as a run named after the file path on the
merge of pull request #1 (run 35477735783, zero jobs), and Dependabot's
github-actions updater failed on the same file (dependency_file_not_parseable,
job 1583380179). Reproduced locally with a YAML parser at line 173, column 25.

No gate step parses the workflow files, so the gate was green on a workflow
GitHub could not read. That is a rule that could be an enforcer and is not
one yet; recorded as a follow-up for the next slice rather than added here.

Signed-off-by: Ayla Croft <aylacroft@proton.me>

Author: HackTuah

.github/workflows/package.yml

@@ -170,7 +170,7 @@ jobs:
       # --no-halt is what makes the exit mean anything. Burrito launches the release as
       # `-s elixir start_cli`, and the Elixir CLI halts when its command list is empty, so
       # without --no-halt the binary exits 0 on its own and `--smoke` proves nothing.
-      - name: Smoke test: boots, serves, exits by itself, leaves nothing behind
+      - name: "Smoke test: boots, serves, exits by itself, leaves nothing behind"
         if: runner.os != 'Windows'
         shell: bash
         run: |