bump linux-circus
bump linux-circus

[fixes #81526514]

Submodule src/github.com/cloudfoundry-incubator/linux-circus ce5bf74..1cec602:
  > Removed race between test invocation and writing the yaml file
  > Avoid test pollution from randomized soldier test

Signed-off-by: Nick Wade <0ae7801e1450b93d494baac68f1ed62bce32d907@pivotal.io>

cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release