Ensure that we don't add balancees with no health check runs if there is a health check defined on it

Change test behavior

provider/marathon.go

@@ -264,6 +264,9 @@ func (provider *Marathon) taskFilter(task marathon.Task, applications *marathon.
 					return false
 				}
 			}
+		} else {
+			log.Debugf("Filtering marathon task %s with defined healthcheck as no healthcheck has run yet", task.AppID)
+			return false
 		}
 	}
 	return true

provider/marathon_test.go

@@ -629,7 +629,7 @@ func TestMarathonTaskFilter(t *testing.T) {
 					},
 				},
 			},
-			expected:         true,
+			expected:         false,
 			exposedByDefault: true,
 		},
 		{