Don't release centos7 aarch64 volume
We ended up not creating centos7 arm64 wheels and don't have this
volume, don't try and release it.
# CentOS
- role: release-afs-volume
afs_volume: mirror.wheel.cent7x64
- - role: release-afs-volume
- afs_volume: mirror.wheel.cent7a64
- role: release-afs-volume
afs_volume: mirror.wheel.cent8x64
