Remove centos copy-on-write backed tests

BTRFS support is absent from RHEL8, and both btrfs and overlayfs
tests are currently broken, possibly since centos 7.6. This patch
unblocks other work whilst leaving the centos dir backed test in
support of existing containerised deployments.

Change-Id: Ib117ad76ca2bd5521d16e02206cb5f5b9f248bf2

zuul.d/jobs.yaml

@@ -71,13 +71,6 @@
     vars:
       tox_env: btrfs
 
-- job:
-    name: openstack-ansible-lxc-btrfs-centos-7
-    parent: openstack-ansible-lxc-container-create
-    nodeset: centos-7
-    vars:
-      tox_env: btrfs
-
 - job:
     name: openstack-ansible-lxc-machinectl-ubuntu-bionic
     parent: openstack-ansible-lxc-container-create
@@ -128,13 +121,6 @@
     vars:
       tox_env: ofs
 
-- job:
-    name: openstack-ansible-lxc-overlayfs-centos-7
-    parent: openstack-ansible-lxc-container-create
-    nodeset: centos-7
-    vars:
-      tox_env: ofs
-
 - job:
     name: openstack-ansible-lxc-zfs-ubuntu-bionic
     parent: openstack-ansible-lxc-container-create

zuul.d/project.yaml

@@ -25,7 +25,6 @@
         - openstack-ansible-lxc-dir-opensuse-150
         - openstack-ansible-lxc-dir-ubuntu-bionic
         - openstack-ansible-lxc-btrfs-ubuntu-bionic
-        - openstack-ansible-lxc-btrfs-centos-7
         - openstack-ansible-lxc-btrfs-opensuse-423
         - openstack-ansible-lxc-btrfs-opensuse-150
         - openstack-ansible-lxc-machinectl-ubuntu-bionic
@@ -33,7 +32,6 @@
         - openstack-ansible-lxc-machinectl-opensuse-423
         - openstack-ansible-lxc-machinectl-opensuse-150
         - openstack-ansible-lxc-overlayfs-ubuntu-bionic
-        - openstack-ansible-lxc-overlayfs-centos-7
         - openstack-ansible-lxc-overlayfs-opensuse-423
         - openstack-ansible-lxc-overlayfs-opensuse-150
         - openstack-ansible-lxc-zfs-ubuntu-bionic