auth token creation is more resilient.
auth token creation is more resilient.

- do not fail if auth token already exists
- do not delete auth token after tests. since this only runs on ci we
  may want to manually test the service.  leaving the auth token in the
  system makes this easier.

cloudfoundry-incubator/v1-dummy-broker-release,cloudfoundry-attic/v1-dummy-broker-release,cloudfoundry-attic/v1-dummy-broker-release,cloudfoundry-incubator/v1-dummy-broker-release,cloudfoundry-incubator/v1-dummy-broker-release,cloudfoundry-incubator/v1-dummy-broker-release,cloudfoundry-attic/v1-dummy-broker-release,cloudfoundry-attic/v1-dummy-broker-release