Fix test_dispatch_opcode_update unit test
Fix test_dispatch_opcode_update unit test

This patch corrects and re-enables the test_dispatch_opcode_update
unit test. The test was incorrect previously by passing a A record type (1)
instead of the required SOA type (6) per RFC 2136 section 2.3.
The dnspython module >=2.0.0 now checks for this and caused the failure.

Change-Id: I19f8c7147c7b58c01adc7c3cfc445edb53f6cdae

openstack/designate,openstack/designate,openstack/designate