update tcp-echo-server.c and asio.c

- example `tcp-echo-server.c` buggy adding `yield()` to `stream_handler` function, will make example execute as expected in tls mode

** general bug/issue with `raii` future calls, libuv threading calls and openssl bio calls, will stale/hang, meaning  never coro switch to another coroutine, the problem shows itself with `use_certificate` function  **

Author: TheTechsTech

examples/tcp-echo-server.c

@@ -5,7 +5,6 @@
 
 void new_connection(uv_stream_t *socket) {
 	string data = stream_read(socket);
-	printf(CLR_LN"%s\n", data);
 	if (data)
 		stream_write(socket, data);
 }
@@ -17,8 +16,8 @@ int uv_main(int argc, char **argv) {
 	string_t host = is_secure ? "tls://127.0.0.1:%d" : "0.0.0.0:%d";
 
 	if (snprintf(addr, sizeof(addr), host, DEFAULT_PORT)) {
-		//if (is_secure)
-		//	use_certificate(nullptr, 0);
+		if (is_secure)
+			use_certificate(nullptr, 0);
 
 		server = stream_bind(addr, 0);
         while (server) {

src/asio.c

@@ -1460,6 +1460,7 @@ static void_t stream_client(params_t args) {
 		uv_handle_set_data(handler(client), (void_t)uv->tls->uv_args);
 		defer((func_t)uv_arguments_free, uv->tls->uv_args);
 		defer(tls_close_free, uv->tls);
+		yield();
 	} else {
         uv_handle_set_data(handler(client), nullptr);
         defer(uv_close_free, client);