Remove doJumpToPage method on MyBatisPagingItemReader

Fixes gh-739

Author: kazuki43zoo

src/main/java/org/mybatis/spring/batch/MyBatisPagingItemReader.java

@@ -130,9 +130,4 @@ protected void doReadPage() {
     results.addAll(sqlSessionTemplate.selectList(queryId, parameters));
   }
 
-  @Override
-  protected void doJumpToPage(int itemIndex) {
-    // Not Implemented
-  }
-
 }