ci: 🎡 add basic slack notification

.github/workflows/ci-main.yml

@@ -58,3 +58,13 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
           HUSKY: 0
+
+      - name: Post release notes to slack
+        # if: steps.changesets.outputs.published == 'true'
+        id: slack
+        uses: slackapi/slack-github-action@v1.25.0
+        with:
+          channel-id: ${{ secrets.SLACK_CHANNEL_ID }}
+          slack-message: "GitHub build result: ${{ job.status }}\n${{ github.event.pull_request.html_url || github.event.head_commit.url }}"
+        env:
+          SLACK_BOT_TOKEN: ${{ secrets.SLACK_BOT_TOKEN }}