When we use manila client to create a share type or share group
type, the is_default value is always empty, this patch is to fix
this issue.
Depends-On: Ia8bcb632591fc0b5438847b22ec59c2039ecf5f1
Change-Id: Ib264d8422fe57701f990cbbf7ea5d1e90b8b0008
Closes-bug: #1743941