gh-36231: fix typo in documentation
    
We fix a typo in the documentation of the method `post_compose` in
`sage.categories.map`

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### ⌛ Dependencies
    
URL: #36231
Reported by: Xavier Caruso
Reviewer(s): Travis Scrimshaw

Author: Release Manager

src/sage/categories/map.pyx

@@ -1092,7 +1092,7 @@ cdef class Map(Element):
         - ``self`` -- a Map in some ``Hom(X, Y, category_right)``
         - ``left`` -- a Map in some ``Hom(Y, Z, category_left)``
 
-        Returns the composition of ``self`` followed by ``right`` as a
+        Returns the composition of ``self`` followed by ``left`` as a
         morphism in ``Hom(X, Z, category)`` where ``category`` is the
         meet of ``category_left`` and ``category_right``.