Extracting substring indexes to variables

Author: dabico

src/main/java/ch/usi/si/seart/treesitter/OffsetTreeCursor.java

@@ -289,7 +289,9 @@ public int hashCode() {
         @Override
         public String toString() {
             String original = node.toString();
-            String data = original.substring(5, original.length() - 1);
+            int lower = 5;
+            int upper = original.length() - 1;
+            String data = original.substring(lower, upper);
             return String.format(
                     "OffsetNode(%s, row: %d, column: %d)",
                     data, offset.getRow(), offset.getColumn()