Revert "Pass ZUUL_* env vars through tox"
Revert "Pass ZUUL_* env vars through tox"

This reverts commit b70bbeb5c7a93a0ae0fad067359f35909dab8afe.

This is no longer needed with the dependent commit merged.

Change-Id: I22fad4995cb379009a1fac9be25dd580e1aacee5
Depends-On: Iacba1611e5c50fbccd6ae700b3456028b142fc5c

Tesora/tesora-project-config,dongwenjuan/project-config,openstack-infra/project-config,noorul/os-project-config,noorul/os-project-config,dongwenjuan/project-config,Tesora/tesora-project-config,openstack-infra/project-config