Fix typo: InMemoryMessageRespository -> InMemoryMessageRepository

Closes gh-1671

spring-boot-samples/spring-boot-sample-web-ui/src/main/java/sample/ui/InMemoryMessageRepository.java

@@ -23,7 +23,7 @@ import java.util.concurrent.atomic.AtomicLong;
 /**
  * @author Dave Syer
  */
-public class InMemoryMessageRespository implements MessageRepository {
+public class InMemoryMessageRepository implements MessageRepository {
 
 	private static AtomicLong counter = new AtomicLong();