ci: add Discord notifiction on failure

Depends on: status-im/status-jenkins-lib#83

Signed-off-by: Jakub Sokołowski <jakub@status.im>

Author: jakubgs

ci/Jenkinsfile

@@ -1,5 +1,5 @@
 #!/usr/bin/env groovy
-library 'status-jenkins-lib@v1.8.1'
+library 'status-jenkins-lib@add-discord-lib'
 
 pipeline {
 
@@ -181,6 +181,12 @@ pipeline {
       ])
       updateGitHubStatus()
     } }
+    failure { script {
+      discord.send(
+        header: '**Desktop E2E test failure!**',
+        cred: 'discord-status-desktop-e2e-webhook',
+      )
+    } }
     cleanup { cleanWs() }
   }
 }