Spring Cloud Gateway single thread server issue

[Johnny850807]

Describe the bug
Currently the gateway uses a simple server to launch the server, which actually uses only a single thread.

This is too simple to hold concurrent requests, as it will in turn cause a deadlock.

For example, if gateway redirects a request to itself, a circular dependency is constructed.
Because the gateway is waiting for the downstream service to fulfill the request, but the downstream service is gateway itself, where single threading can't take the second request.