catch DriverLoadFailure for get_transport optional

new oslo.messaging 5.2.0 release will raise
oslo_messaging.transport.DriverLoadFailure if no existent transport
driver, hence breaks our code and unit test as well.

This patch fixes it by adding DriverLoadFailure to catch list.

Also:

tempest: import ImagesClient as ImagesClientV2

This commit [1] renamed ImagesClientV2 to ImagesClient so Ceilometer
Tempest tests do not work anymore.

[1] https://github.com/openstack/tempest/commit/2fea405bd6ea8674c8daaf8ebb788ae33d52c976

Change-Id: I02b5d1b3f4a9169cbf428a5eff9c6705494741af
Closes-Bug: #1588151
(cherry picked from commit d7f8ce94e433da8af3660ecf52715a04c221fde5)
(cherry picked from commit f6b2406fffdd4deae508b9f251691fe9b70cb1ee)
1 file changed
tree: 60ed8c2753f6f66c47350306f96be3bc46032eef
  1. ceilometer/