bpo-33892: Doc: Use gender neutral words (GH-7770)

(cherry picked from commit 5092439c2cb32112a5869b138011d38491db90a9)

Co-authored-by: Andrés Delfino <adelfino@gmail.com>
diff --git a/Doc/c-api/memory.rst b/Doc/c-api/memory.rst
index 258898d..2b9fb73 100644
--- a/Doc/c-api/memory.rst
+++ b/Doc/c-api/memory.rst
@@ -35,7 +35,7 @@
 
 It is important to understand that the management of the Python heap is
 performed by the interpreter itself and that the user has no control over it,
-even if she regularly manipulates object pointers to memory blocks inside that
+even if they regularly manipulate object pointers to memory blocks inside that
 heap.  The allocation of heap space for Python objects and other internal
 buffers is performed on demand by the Python memory manager through the Python/C
 API functions listed in this document.