@PostConstruct
    public void init() {
        initGrpClientConstructorInjections();
    }
Creates a new GrpcClientBeanPostProcessor with the given ApplicationContext.

@param applicationContext The application context that will be used to get lazy access to the
       {@link GrpcChannelFactory} and {@link StubTransformer}s.
grpc-client-spring-boot-starter/src/main/java/net/devh/boot/grpc/client/inject/GrpcClientBeanPostProcessor.java