[3.11] Fixing typo in DocTestRunner docs (GH-112326) (GH-113098)

(cherry picked from commit b3c2126)

Co-authored-by: Daniel Wysocki <[email protected]>

Author: miss-islington

Doc/library/doctest.rst

@@ -1475,7 +1475,7 @@ DocTestRunner objects
    For more information, see section :ref:`doctest-options`.
 
 
-   :class:`DocTestParser` defines the following methods:
+   :class:`DocTestRunner` defines the following methods:
 
 
    .. method:: report_start(out, test, example)