Fix checkstyle violation

Fix public constructor accidentally added in commit 72862b56.

See gh-10387

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/flyway/FlywayAutoConfiguration.java

@@ -219,7 +219,7 @@ public class FlywayAutoConfiguration {
 
 		private final DataSource dataSource;
 
-		public LocationResolver(DataSource dataSource) {
+		LocationResolver(DataSource dataSource) {
 			this.dataSource = dataSource;
 		}