chore(e2e): Add slack message on e2e test failure (#3070)

* chore(e2e): Add slack message on test failure

* chore(e2e): Remove deprecated variable

* CR: only run in boundary-ui

.github/workflows/test-e2e-admin-ui.yaml

@@ -189,3 +189,13 @@ jobs:
           export ENOS_VAR_enos_user=$GITHUB_ACTOR && \
           export ENOS_VAR_aws_ssh_private_key_path=~/.ssh/github_enos && \
           enos scenario destroy --timeout 60m0s --chdir ./support/src/${{matrix.folder_name}}/enos ${{matrix.enos_scenario}} builder:local
+
+      - name: Send Slack message on failure
+        uses: slackapi/slack-github-action@91efab103c0de0a537f72a35f6b8cda0ee76bf0a # v2.1.1
+        if: ${{ failure() && github.repository == 'hashicorp/boundary-ui' }}
+        with:
+          method: chat.postMessage
+          token: ${{ secrets.SLACK_BOT_TOKEN }}
+          payload: |
+            channel: ${{ secrets.SLACK_CHANNEL_ID }}
+            text: ":x: admin ui e2e tests failed: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}\n*Branch:* ${{ github.repository }}:${{ github.event.ref }}"