Fix accidental switch from Println to Printf

pkg/util/downloader.go

@@ -72,7 +72,7 @@ func (f DefaultDownloader) CacheMinikubeISOFromURL(isoURL string) error {
 		options.ChecksumHash = crypto.SHA256
 	}
 
-	fmt.Printf("Downloading Minikube ISO")
+	fmt.Println("Downloading Minikube ISO")
 	if err := download.ToFile(isoURL, f.GetISOCacheFilepath(isoURL), options); err != nil {
 		return errors.Wrap(err, isoURL)
 	}