minor #6693 Add missing parameter (rodnaph)

This PR was submitted for the 3.1 branch but it was merged into the 2.8 branch instead (closes #6693).

Discussion
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Add missing parameter

$routes->import was missing the $prefix parameter.

Commits
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1397bac Add missing parameter

Author: xabbuh

cookbook/configuration/micro-kernel-trait.rst

@@ -201,7 +201,7 @@ to hold the kernel. Now it looks like this::
             // load the annotation routes
             $routes->mount(
                 '/',
-                $routes->import(__DIR__.'/../src/App/Controller/', 'annotation')
+                $routes->import(__DIR__.'/../src/App/Controller/', '/', 'annotation')
             );
         }
     }