bug #6377 Update "bootstrap.php.cache" to "autoload.php" (guilliamxavier)

This PR was merged into the 2.8 branch.

Discussion
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Update "bootstrap.php.cache" to "autoload.php"

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | 2.8
| Fixed tickets |

Update `testing.rst` for version 2.8 accordingly after change symfony/symfony-standard@747a384#diff-d81c0bc884e8d2b4407434a5aef33c0a

Commits
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aa6fb92 Update "bootstrap.php.cache" to "autoload.php"

Author: weaverryan

book/testing.rst

@@ -92,7 +92,7 @@ of your bundle::
     directory.
 
 Just like in your real application - autoloading is automatically enabled
-via the ``bootstrap.php.cache`` file (as configured by default in the
+via the ``autoload.php`` file (as configured by default in the
 ``app/phpunit.xml.dist`` file).
 
 Running tests for a given file or directory is also very easy: