bump diego-ssh
bump diego-ssh

[delivers #96032148]

Submodule src/github.com/cloudfoundry-incubator/diego-ssh c2ddb08..c904521:
  > Emit a log message after a successful connect

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