Increase the Tenks nodes to 3 GiB ram and force `cpu_mode: maximum` so
the CentOS Stream IPA no longer errors with "Fatal glibc error: CPU does
not support x86-64-v2", like in kolla-ansible [1].
[1] https://review.opendev.org/c/openstack/kolla-ansible/+/965244
Change-Id: If0352355db140b5c96776a9380af9afa933b9af3
Co-Authored-By: Bartosz Bezak <bartosz@stackhpc.com>
Signed-off-by: Pierre Riteau <pierre@stackhpc.com>