github: Skip FTP SNAT orig tuple tests due to broken Ubuntu kernel.

GitHub Actions moved to the new 6.8.0-1014-azure openvswitch#16~22.04.1-Ubuntu
kernel that contains a known bug, but doesn't have a fix (presumably
because the fix is not in 6.8 branch, since 6.8 kernel version is not
supported upstream).

The fix is in commit a23ac973f67f ("openvswitch: get related ct labels
from its master if it is not confirmed").  Turn off these tests in CI
until the kernel is fixed.

This skips the tests for the userspace datapath as well, but hopefully
we'll be able to revert this change soon, so I didn't want to create
extra infrastructure for this workaround.

Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

tests/system-traffic.at

@@ -7083,6 +7083,12 @@ dnl Checks the implementation of conntrack with FTP ALGs in combination with
 dnl NAT, using the provided flow table.
 m4_define([CHECK_FTP_NAT],
    [AT_SETUP([conntrack - FTP $1])
+    m4_if(m4_index([$1], [orig tuple]), -1, [], [
+      dnl 6.8.0-1014-azure #16~22.04.1-Ubuntu kernel in GitHub Actions
+      dnl contains a known conntrack bug, but doesn't have a fix for it:
+      dnl   a23ac973f67f ("openvswitch: get related ct labels from its master
+      dnl                  if it is not confirmed")
+      OVS_CHECK_GITHUB_ACTION()])
     AT_SKIP_IF([test $HAVE_FTP = no])
     AT_SKIP_IF([test $HAVE_LFTP = no])
     CHECK_CONNTRACK()