Add sleep to CI hooks to avoid races

Manila CI hooks for DHSS=False job with the Generic driver wait for
service instance availability and right after it becomes available
returns control to caller. And caller can run tests with creation of
shares immediately. But, in this case, we can face race conditions when
manila-share service requires some time to inform manila-scheduler.
So, add 'sleep 10' operation to be executed after reaching 'available'
state by service instance.It should be enough to overcome races.

Change-Id: Ie4ae231701edaab319c9012e476d1f63e3806499

contrib/ci/common.sh

@@ -69,4 +69,8 @@ function manila_wait_for_drivers_init {
     # First argument is expected to be file path to Manila config
 
     manila_wait_for_generic_driver_init $1
+
+    # Sleep to make manila-share service notify manila-scheduler about
+    # its capabilities on time.
+    sleep 10
 }