Remove epoll instances config

tests/test_server_connection_return.cpp

@@ -42,7 +42,6 @@ TEST_CASE(
     "Server correctly handles connection ownership transfer via pipeline") {
   weaseldb::Config config;
   config.server.io_threads = 1;
-  config.server.epoll_instances = 1;
 
   StaticThreadPipeline<Message, WaitStrategy::WaitIfStageEmpty, 1> pipeline{10};
   EchoHandler handler{pipeline};