Switch filesystem mount test from btrfs to ext4

BTRFS is not available on centos-8 so switch the test to ext4 instead.

Change-Id: I9bcbbe4dd2ed94f2c6db1af5f927e68f079c8a7a

tests/test-create-ext4-dev.yml

@@ -13,17 +13,12 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-- name: Configure BTRFS sparse file
+- name: Configure ext4 sparse file
   hosts: localhost
   user: root
   become: true
   connection: local
   tasks:
-    - name: Install BTRFS packages
-      package:
-        name: "{{ btrfs_package[ansible_pkg_mgr | lower] }}"
-        state: present
-
     - name: Create base directories
       file:
         path: "/var/lib"
@@ -37,12 +32,7 @@
 
     - name: Format the sparse file
       filesystem:
-        fstype: btrfs
+        fstype: ext4
         dev: /var/lib/sparse-file.img
       when:
         - sparse_file  is changed
-  vars:
-    btrfs_package:
-      apt: "btrfs-tools"
-      yum: "btrfs-progs"
-      zypper: "btrfsprogs"

tests/test.yml

@@ -18,7 +18,7 @@
 
 - import_playbook: test-create-nfs-dev.yml
 
-- import_playbook: test-create-btrfs-dev.yml
+- import_playbook: test-create-ext4-dev.yml
 
 - name: Playbook for role testing
   hosts: localhost
@@ -46,7 +46,7 @@
     systemd_mounts:
       - what: '/var/lib/sparse-file.img'
         where: '/var/lib/sparse-file'
-        type: 'btrfs'
+        type: 'ext4'
         options: 'loop'
         state: 'started'
         enabled: true