remove duplicate check

Signed-off-by: Xiang Dai <764524258@qq.com>

pkg/downloader/manager.go

@@ -406,7 +406,6 @@ func (m *Manager) getRepoNames(deps []*chartutil.Dependency) (map[string]string,
 			missing = append(missing, dd.Repository)
 		}
 	}
-	if len(missing) > 0 {
 	if len(missing) > 0 {
 		errorMessage := fmt.Sprintf("no repository definition for %s. Please add them via 'helm repo add'", strings.Join(missing, ", "))
 		// It is common for people to try to enter "stable" as a repository instead of the actual URL.
@@ -425,7 +424,6 @@ repository, use "https://kubernetes-charts.storage.googleapis.com/" or "@stable"
 		}
 		return nil, errors.New(errorMessage)
 	}
-	}
 	return reposMap, nil
 }