minor #13876 Update testing.rst (zairigimad)

This PR was submitted for the 5.0 branch but it was merged into the 4.4 branch instead.

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Update testing.rst

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577ab9f Update testing.rst

Author: javiereguiluz

testing.rst

@@ -100,7 +100,7 @@ of your application::
 .. note::
 
     By convention, the ``tests/`` directory should replicate the directory
-    of your bundle for unit tests. So, if you're testing a class in the
+    of your application for unit tests. So, if you're testing a class in the
     ``src/Util/`` directory, put the test in the ``tests/Util/``
     directory.