Add tests for mixed IP networks UDP members

Added api tests (specific to the amphora driver) that ensure that:
- User cannot add member with a different IP protocol version than the
  VIP IP protocol version in UDP load balancers.
- User can add member with a different IP protocol in non-UDP load
  balancers.

Story: 2005876
Task: 34779

Change-Id: Ia79d85b4566c2d2ef102a3381e6e3cc8d5328ebc
1 file changed