remote manifest test

Enable remove manifest tests. Skip --purge test because remote does not support it.

Signed-off-by: Qi Wang <qiwan@redhat.com>

pkg/api/handlers/libpod/manifests.go

@@ -151,6 +151,7 @@ func ManifestPush(w http.ResponseWriter, r *http.Request) {
 	}
 	sc := image.GetSystemContext(rtc.Engine.SignaturePolicyPath, "", false)
 	opts := manifests.PushOptions{
+		Store:              runtime.GetStore(),
 		ImageListSelection: copy2.CopySpecificImages,
 		SystemContext:      sc,
 	}