do not autoinstall IWC on umsa

Author: martenson

.github/workflows/update_iwc.yml

@@ -25,7 +25,7 @@ jobs:
           ${{ fromJSON(
                 github.event_name == 'workflow_dispatch'
                 && format('["{0}"]', github.event.inputs.instance)
-                || '["galaxy-qa1.galaxy.cloud.e-infra.cz","usegalaxy.cz","galaxy-umsa.grid.cesnet.cz"]'
+                || '["galaxy-qa1.galaxy.cloud.e-infra.cz","usegalaxy.cz"]'
                ) }}
     steps:
       - uses: actions/setup-python@v5