feat: suppress the output of createApp

A git push requires that the first four bytes should be the line length, so not suppressing the output results in a partially failed deploy.

https://stackoverflow.com/a/8175315/1515875

plugins/apps/functions.go

@@ -155,5 +155,7 @@ func maybeCreateApp(appName string) error {
 		return fmt.Errorf("Re-enable app auto-creation or create an app with 'dokku apps:create %s'", appName)
 	}
 
-	return createApp(appName)
+	return common.SuppressOutput(func() error {
+		return createApp(appName)
+	})
 }