refactor: code review

Author: Aliaksie

mcp/src/main/java/io/modelcontextprotocol/client/transport/FlowSseClient.java

@@ -7,10 +7,8 @@
 import java.net.http.HttpClient;
 import java.net.http.HttpRequest;
 import java.net.http.HttpResponse;
-import java.util.Map;
 import java.util.concurrent.Flow;
 import java.util.concurrent.atomic.AtomicReference;
-import java.util.function.BiConsumer;
 import java.util.function.Function;
 import java.util.regex.Pattern;