ci: merge release notification action (#64)

Author: hamzamahmood

.github/workflows/release-notification.yml

@@ -39,3 +39,12 @@ jobs:
           tag: ${{ steps.tag_version.outputs.new_tag }}
           name: Release Version ${{ github.event.inputs.Version }}
           body: ${{ steps.tag_version.outputs.changelog }}
+      
+      - name: Send slack notification
+        id: slack
+        uses: slackapi/[email protected]
+        with:
+            channel-id: 'C012YFE3D6D'
+            slack-message: "core-lib-csharp release has been triggered!"
+        env:
+            SLACK_BOT_TOKEN: ${{ secrets.SLACK_BOT_TOKEN }}