removed unused import

src/main/java/com/zaxxer/hikari/pool/HikariPool.java

@@ -28,7 +28,6 @@ import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.ThreadLocalRandom;
 import java.util.concurrent.ThreadPoolExecutor;
-import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import org.slf4j.Logger;