public void setImmediateConnectTimeout(final Duration immediateConnectTimeout) {
        if (immediateConnectTimeout.isNegative()) {
            throw new IllegalArgumentException("Timeout can't be negative");
        }
        this.immediateConnectTimeout = immediateConnectTimeout;
    }
If set to a positive duration instructs the client to connect to the gRPC endpoint when the GRPC stub is created.
As a result the application startup will be slightly slower due to connection process being executed
synchronously up to the maximum to connection timeout. If the connection fails, the stub will fail to create with
an exception which in turn causes the application context startup to fail. Defaults to {@code 0}.

@param immediateConnectTimeout Connection timeout at application startup.
grpc-client-spring-boot-starter/src/main/java/net/devh/boot/grpc/client/config/GrpcChannelProperties.java