minor #12435 Remove "mocking" to better reflect the subject. (lex0r)

This PR was submitted for the master branch but it was merged into the 4.3 branch instead (closes #12435).

Discussion
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Remove "mocking" to better reflect the subject.

This section is about doing a functional (or perhaps integration?) testing with the real (not mocked) objects, therefore using "mocking" in the title is not correct, especially because it echoes the previous section where actual mock objects are used.

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Commits
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6a97f4a Remove "mocking" to better reflect the subject.

Author: javiereguiluz

testing/database.rst

@@ -200,7 +200,7 @@ the employee which gets returned by the ``Repository``, which itself gets
 returned by the ``EntityManager``. This way, no real class is involved in
 testing.
 
-Mocking a Doctrine Repository in Functional Tests
+Functional Testing of A Doctrine Repository
 -------------------------------------------------
 
 In :ref:`functional tests <functional-tests>` you'll make queries to the