CI: temporarily disable CentOS/AArch64 testing
CI: temporarily disable CentOS/AArch64 testing

Python is crashing on CI, infra team is investigating.

Change-Id: I07385be75a7fdc35612bf3f4b3d6190cced8a0e5

stackforge/kolla,stackforge/kolla,openstack/kolla,openstack/kolla,stackforge/kolla