fix(ci): publish when the release PR merges, not when a changeset lands (#8)

changesets/action runs `changeset version` in the working directory before it
pushes the release branch, so the publish step that follows it in the same job
sees a tree that is already bumped. 0.2.0 went out the moment #6 merged, while
its release PR was still open - and that PR's own run then had nothing left to
do. Gating on `has-changesets` puts the release back behind the merge.

Author: upupming

.github/workflows/release.yml

@@ -35,6 +35,7 @@ jobs:
         run: echo "date=$(date -u +'%Y-%m-%d %H:%M:%S')" >> "$GITHUB_OUTPUT"
 
       - name: Attempt to release
+        id: changesets
         uses: changesets/action@8488615a623b1b9c987934bb89eae8af6a946ac1 # v2.1.1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -43,6 +44,7 @@ jobs:
           commit-message: "chore: release ${{ steps.date.outputs.date }}"
 
       - name: Publish packages
+        if: steps.changesets.outputs.has-changesets == 'false'
         run: >
           pnpm --recursive --filter "./packages/*" publish
           --no-git-checks --access public