Fix minor typo in nodeIncrementalSort.c.
Author: Vignesh C
Backpatch-through: 13, where it was introduced
Discussion:
* into the second mode if we believe it's beneficial.
*
* Sorting incrementally can potentially use less memory, avoid fetching
- * and sorting all tuples in the the dataset, and begin returning tuples
- * before the entire result set is available.
+ * and sorting all tuples in the dataset, and begin returning tuples before
+ * the entire result set is available.
*
* The hybrid mode approach allows us to optimize for both very small
* groups (where the overhead of a new tuplesort is high) and very large
