Do not run route-registrar tests in parallel
Do not run route-registrar tests in parallel

- These tests are badly written and usually fail when run in parallel
- Since the module has been untouched for some time, we're opting to not
  run tests in parallel rather than fixing the tests to be more robust

[#108793976]

Signed-off-by: Lyle Franklin <31e283733c7a4b3b6cb03b95ab535671c2112bbe@pivotal.io>

cloudfoundry-incubator/route-registrar,cloudfoundry-incubator/route-registrar