Cirrus: Temporarily disable testing on Ubuntu 19

The images build correctly but neither integration or remote client
tests pass.  Temporarily disable Ubuntu 19 testing until both are
ready to be supported.

Signed-off-by: Chris Evich <cevich@redhat.com>

.cirrus.yml

@@ -328,7 +328,7 @@ testing_task:
             # Images are generated separately, from build_images_task (below)
             image_name: "${FEDORA_CACHE_IMAGE_NAME}"
             image_name: "${PRIOR_FEDORA_CACHE_IMAGE_NAME}"
-            image_name: "${UBUNTU_CACHE_IMAGE_NAME}"
+            # TODO: image_name: "${UBUNTU_CACHE_IMAGE_NAME}"
             image_name: "${PRIOR_UBUNTU_CACHE_IMAGE_NAME}"
 
     timeout_in: 120m
@@ -604,7 +604,7 @@ verify_test_built_images_task:
             PACKER_BUILDER_NAME: "fedora-30"
             PACKER_BUILDER_NAME: "xfedora-30"
             PACKER_BUILDER_NAME: "ubuntu-18"
-            PACKER_BUILDER_NAME: "ubuntu-19"
+            # TODO support $UBUNTU_CACHE_IMAGE_NAME: PACKER_BUILDER_NAME: "ubuntu-19"
 
     networking_script: '${CIRRUS_WORKING_DIR}/${SCRIPT_BASE}/networking.sh'
     environment_script: '$SCRIPT_BASE/setup_environment.sh |& ${TIMESTAMP}'