public void refreshFromExternal() {
        this.syncContext.execute(() -> {
            if (isActive()) {
                resolve();
            }
        });
    }
Triggers a refresh on the listener from non-grpc threads. This method can safely be called, even if the listener
hasn't been started yet.

@see #refresh()
grpc-client-spring-boot-starter/src/main/java/net/devh/boot/grpc/client/nameresolver/DiscoveryClientNameResolver.java