DOCS-960 optimizer logic- copy edit, remove errant the

Author: kay-kim

source/core/read-operations.txt

@@ -582,7 +582,7 @@ To create a new query plan, the query optimizer:
      <unordered query plan>`, there is a single common results buffer.
 
    - If the candidate plans include *both* :term:`ordered query plans
-     <ordered query plan>` and the :term:`unordered query plans
+     <ordered query plan>` and :term:`unordered query plans
      <unordered query plan>`, there are two common results buffers, one
      for the ordered plans and the other for the unordered plans.