minor symfony#26592 [FrameworkBundle] Use a::b notation in ControllerTrait docblock (hacfi)

This PR was merged into the 4.1-dev branch.

Discussion
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[FrameworkBundle] Use `a::b` notation in ControllerTrait docblock

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | symfony#26085
| License       | MIT
| Doc PR        | already documented

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Replaced the deprecated the bundle notation with the new `a::b` notation in the docblock of `ControllerTrait::forward`

Commits
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973c5ec [FrameworkBundle] Use `a::b` notation in ControllerTrait docblock

Author: nicolas-grekas

src/Symfony/Bundle/FrameworkBundle/Controller/ControllerTrait.php

@@ -76,7 +76,7 @@ protected function generateUrl(string $route, array $parameters = array(), int $
     /**
      * Forwards the request to another controller.
      *
-     * @param string $controller The controller name (a string like BlogBundle:Post:index)
+     * @param string $controller The controller name (a string like Bundle\BlogBundle\Controller\PostController::indexAction)
      *
      * @final
      */