QE: Kill the openSUSE Leap repo sync

See SUSE/spacewalk#22336

testsuite/features/reposync/srv_wait_for_reposync.feature

@@ -16,9 +16,5 @@ Feature: Wait for reposync activity to finish in CI context
   Scenario: Kill running reposyncs or wait for them to finish
     When I kill all running spacewalk-repo-sync, excepted the ones needed to bootstrap
 
-@uyuni
-  Scenario: Sync openSUSE Leap 15.4 product, including Uyuni Client Tools
-    When I call spacewalk-repo-sync to sync the parent channel "opensuse_leap15_4-x86_64"
-
   Scenario: Wait until all synchronized channels have finished
     When I wait until all synchronized channels have finished

testsuite/features/support/commonlib.rb

@@ -30,19 +30,14 @@ def generate_temp_file(name, content)
 # This is a safety net only, the best thing to do is to not start the reposync at all.
 def compute_channels_to_leave_running
   # keep the repos needed for the auto-installation tests
-  do_not_kill =
-    if product == 'Uyuni'
-      CHANNEL_TO_SYNCH_BY_OS_VERSION['15.4']
-    else
-      CHANNEL_TO_SYNCH_BY_OS_VERSION['default']
-    end
+  do_not_kill = CHANNEL_TO_SYNCH_BY_OS_VERSION['default']
   [get_target('sle_minion'), get_target('build_host'), get_target('ssh_minion'), get_target('rhlike_minion')].each do |node|
     next unless node
     os_version = node.os_version
     os_family = node.os_family
     next unless ['sles', 'rocky'].include?(os_family)
     os_version = os_version.split('.')[0] if os_family == 'rocky'
-    log 'Can\'t build list of reposyncs to leave running' unless %w[15-SP3 15-SP4 15.4 8].include? os_version
+    log 'Can\'t build list of reposyncs to leave running' unless %w[15-SP3 15-SP4 8].include? os_version
     do_not_kill += CHANNEL_TO_SYNCH_BY_OS_VERSION[os_version]
   end
   do_not_kill.uniq