static ServiceNaming simpleTypeName() {
        return SimpleTypeServiceNaming.INSTANCE;
    }
Returns the {@link ServiceNaming} that returns the simple name of an RPC stub class or
the innermost class from the given service. It is supposed to have a class name without a period.
e.g. {@code HelloService}.
core/src/main/java/com/linecorp/armeria/server/ServiceNaming.java