Since kernel-source commit 18f65dfce6af8bef50878fb80ba29f6d8626a918,
automatically queuing the secure boot certificate isn't happening.

This is because the post.sh changes cause the scriptlet to exit unconditionally
but the secure boot handling adds to the end of the script after the exit:

[...]

# check if something failed
[ $wm2_rc != 0 ] && exit $wm2_rc
exit $rc

# vim: set sts=4 sw=4 ts=8 noet:
if ! command -v mokutil >/dev/null; then
        exit 0
fi

[...]

This change has also been adopted in SLE.