[Xena Jobs] use 'full' tox env

With [1] Xena is being pinned to 33.0.0 and that version
don't have 'multinode' and 'integrated-full' tox envs,
so using 'full'. xena-last tag which have both these envs
can't be used due to[2][3].

Also exclude DHCPAgentSchedulersTestJSON and Multiattach tests as
[4][5] missing in tempest-33.0.0.

[1] https://review.opendev.org/c/openstack/devstack/+/933741
[2] https://review.opendev.org/c/openstack/tempest/+/821732
[3] https://review.opendev.org/c/openstack/tempest/+/873442
[4] https://review.opendev.org/c/openstack/tempest/+/898090
[5] https://review.opendev.org/c/openstack/tempest/+/875372

Needed-By: https://review.opendev.org/c/openstack/devstack/+/933741
Change-Id: I5e82704ae81e5c0ef016fac02d153d6ed003d12b
1 file changed