ci: add Discord notification to sync workflow (#72)

* Initial plan

* ci: add discord notify job to sync workflow

Co-authored-by: Marketen <36164126+Marketen@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Marketen <36164126+Marketen@users.noreply.github.com>

Author: Copilot

.github/workflows/sync.yml

@@ -24,3 +24,11 @@ jobs:
             -e CONSENSUS_CLIENT=${{ github.event.inputs.consensus_client }} \
             -e NETWORK=hoodi \
             ghcr.io/dappnode/staker-test-util/test-runner:latest
+  notify:
+    needs: sync
+    if: always() && needs.sync.result != 'skipped'
+    uses: dappnode/staker-test-util/.github/workflows/notify-discord.yml@main
+    with:
+      result: ${{ needs.sync.result }}
+      test_type: "sync"
+    secrets: inherit