fixup! test(CHANGELOG): add GH action step summaries from check

Author: ErichDonGubler

.github/workflows/changelog.yml

@@ -44,4 +44,4 @@ jobs:
       # NOTE: Keep label name(s) in sync. with `xtask`'s implementation.
       - name: Run `cargo xtask changelog …`
         run: |
-          cargo xtask changelog --emit-github-messages ${{ contains(github.event.issue.labels.*.name, 'changelog: released entry changed') && '--warn-only' || ''  }} "origin/${{ github.event.pull_request.base.ref }}" >> "$GITHUB_STEP_SUMMARY"
+          cargo --quiet xtask changelog --emit-github-messages ${{ contains(github.event.issue.labels.*.name, 'changelog: released entry changed') && '--warn-only' || ''  }} "origin/${{ github.event.pull_request.base.ref }}" 2> >(tee --append "$GITHUB_STEP_SUMMARY" >&2)