Add token validation and Seqera Platform integration to slack config

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: FriederikeHanssen

.github/workflows/cloudtest.yml

@@ -92,10 +92,14 @@ jobs:
           nextflow_config: |
             slack {
               enabled = true
+              validateOnStartup = true
               bot {
                 token = '${{ secrets.NFSLACK_BOT_TOKEN }}'
                 channel = 'sarek_dev'
               }
+              seqeraPlatform {
+                enabled = true
+              }
               onStart {
                 enabled = false
               }