Ignore infra CI env vars
Ignore infra CI env vars

When running tests in the infra CI system, some OS_ environment
variables are defined (e.g., OS_TEST_TIMEOUT, OS_TEST_PATH,
OS_STDERR_CAPTURE, OS_STDOUT_CAPTURE) and this makes o-c-c think
that we are using environment variables for an envvar cloud. In
some rare cases, this can cause tests to fail if they expect
cloud definitions to come only from clouds.yaml. This change
ignores these CI variables.

Change-Id: I6458969b45f5534e1172b9f8ba598d7c536a59b5

openstack/os-client-config,redhat-openstack/os-client-config,openstack/python-openstacksdk,switch-ch/os-client-config,stackforge/python-openstacksdk,dtroyer/python-openstacksdk,dtroyer/os-client-config,openstack/python-openstacksdk,stackforge/python-openstacksdk,dtroyer/python-openstacksdk