Skip boto tests when auth_version is v3

When auth_version is v3, boto clients are not setup by manager
as boto clients can only use v2 identity clients to generate AWS
credentials.

When auth version is v3, boto tests try to run, and fail because
they can't find the clients. They should be skipped instead.

Partially-implements: bp/multi-keystone-api-version-tests
Change-Id: I7281d2c886d123682cefc5b5511c11300af0ca4c
1 file changed