Removes "DDT" module from Designate-Tempest-Plugin

This patch removes DDT module from the code as well as
all *.json files related to it.

Change-Id: I2203d52c4a816dee0960339a8ea3e0ea023b131d

(cherry picked from commit 462e39d73f875e26bab1685f647eab1ea49491d0)
Change-Id: Ied6513e4f75a5392924b66e26bf2bf468906977b

Related-issue: PRODX-34472
Change-Id: I4b9c1c7b8dc712c7649cea94a7b15876ffc181a8
11 files changed