Moved log from INFO to DEBUG, as now the synchronizer is on its own thread it can occur more often than before.

src/main/java/org/qortal/controller/Synchronizer.java

@@ -859,7 +859,7 @@ public class Synchronizer extends Thread {
 		ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
 		if (!blockchainLock.tryLock()) {
 			// Wasn't peer's fault we couldn't sync
-			LOGGER.info("Synchronizer couldn't acquire blockchain lock");
+			LOGGER.debug("Synchronizer couldn't acquire blockchain lock");
 			return SynchronizationResult.NO_BLOCKCHAIN_LOCK;
 		}