private void rewrite() {
        fileSystem.writeFileBlocking(file.getAbsolutePath(), Buffer.buffer(root.encodePrettily()));
        rewriteCompleteSignal();
    }
@author Marc Savy {@literal <marc@rhymewithgravy.com>}
gateway/test/src/test/java/io/apiman/gateway/test/junit/vertx3/ApiToFileRegistry.java