@Override
        protected void attachAuthenticationContext() {
            SecurityContextHolder.setContext(this.securityContext);
        }
Creates a new AuthenticatingServerCallListener which will attach the given security context before delegating
to the given listener.

@param delegate The listener to delegate to.
@param grpcContext The context to attach.
@param securityContext The security context instance to attach.
grpc-server-spring-boot-starter/src/main/java/net/devh/boot/grpc/server/security/interceptors/DefaultAuthenticatingServerInterceptor.java