Indicates using phpunit.xml.dist is preffered

Author: Patrick PawseyVale

components/phpunit_bridge.rst

@@ -573,12 +573,14 @@ If you have installed the bridge through Composer, you can run it by calling e.g
 
 .. tip::
 
-    Set a real env var (not in a :doc:`dotenv </components/dotenv>` file)
-    ``SYMFONY_PHPUNIT_VERSION`` to e.g. ``5.5`` to change the base version
-    of PHPUnit to ``5.5`` instead of the default ``5.3``.
-
-    It's also possible to set this env var in the ``phpunit.xml.dist`` file
-    as e.g. ``<server name="SYMFONY_PHPUNIT_VERSION" value="5.5" />``.
+    It's possible to to change the base version of PHPUnit to e.g. ``5.5``
+    instead of the default ``5.3`` by setting the ``SYMFONY_PHPUNIT_VERSION``
+    env var in the ``phpunit.xml.dist`` file e.g.
+    ``<server name="SYMFONY_PHPUNIT_VERSION" value="5.5" />``. This is the
+    preferred method as it can be committed to your version control repository.
+
+    It's also possible set ``SYMFONY_PHPUNIT_VERSION`` as a real env var
+    (not in a :doc:`dotenv </components/dotenv>` file).
 
 .. tip::