Add unit test for cmd/svcat/broker/describe_cmd.go (#2179)
Add unit test for cmd/svcat/broker/describe_cmd.go (#2179)

Add unit test for cmd/svcat/broker/describe_cmd.go to increase
test coverage
MHBauer/service-catalog,kubernetes-sigs/service-catalog,kubernetes-sigs/service-catalog,kubernetes-sigs/service-catalog,kubernetes-incubator/service-catalog,jboyd01/service-catalog,kubernetes-sigs/service-catalog,jboyd01/service-catalog,MHBauer/service-catalog,jboyd01/service-catalog,kubernetes-incubator/service-catalog,kubernetes-incubator/service-catalog,MHBauer/service-catalog,MHBauer/service-catalog,MHBauer/service-catalog,kubernetes-incubator/service-catalog,jboyd01/service-catalog,kubernetes-sigs/service-catalog,kubernetes-incubator/service-catalog,kubernetes-incubator/service-catalog,jboyd01/service-catalog,MHBauer/service-catalog,kubernetes-sigs/service-catalog,jboyd01/service-catalog