use column names in error message

git-svn-id: https://svn.code.sf.net/p/jackcess/code/jackcess/trunk@1063 f203690c-595d-4dc9-a70b-905162fa7fd2

src/main/java/com/healthmarketscience/jackcess/impl/RelationshipCreator.java

@@ -330,7 +330,7 @@ public class RelationshipCreator extends DBMutator
     }
 
     return CustomToStringStyle.valueBuilder(tableName)
-      .append(null, cols)
+      .append(null, colNames)
       .toString();
   }