app-manager: fix failures on missing Schema.yaml
diff --git a/appmanager/helm.go b/appmanager/helm.go
index 150900e..db60a4b 100644
--- a/appmanager/helm.go
+++ b/appmanager/helm.go
@@ -35,7 +35,7 @@
 	}
 	chart.Chart = *c
 	schema, err := ReadSchema(path.Join(chartDir, "Schema.yaml"))
-	if err != nil && os.IsNotExist(err) {
+	if err != nil && !os.IsNotExist(err) {
 		return nil, err
 	}
 	chart.Schema = schema