Use Loom friendly locking

src/main/java/de/malkusch/km200/http/SerializedHttp.java

@@ -1,30 +1,38 @@
 package de.malkusch.km200.http;
 
 import java.io.IOException;
+import java.util.concurrent.locks.ReentrantLock;
 
 import de.malkusch.km200.KM200Exception;
 
 public final class SerializedHttp implements Http {
 
     private final Http http;
+    private final ReentrantLock lock = new ReentrantLock();
 
     public SerializedHttp(Http http) {
         this.http = http;
     }
 
-    private final Object lock = new Object();
-
     @Override
     public Response get(String path) throws IOException, InterruptedException, KM200Exception {
-        synchronized (lock) {
+        lock.lockInterruptibly();
+        try {
             return http.get(path);
+
+        } finally {
+            lock.unlock();
         }
     }
 
     @Override
     public Response post(String path, byte[] body) throws IOException, InterruptedException, KM200Exception {
-        synchronized (lock) {
+        lock.lockInterruptibly();
+        try {
             return http.post(path, body);
+
+        } finally {
+            lock.unlock();
         }
     }
 }