This PR was squashed before being merged into the 3.3 branch (closes#8644).Discussion----------Removed an uneeded deprecation noticeSpotted while working on#8643.Commits-------a96a633 Removed an uneeded deprecation notice

This PR was squashed before being merged into the 4.0 branch (closes#8643).Discussion----------Updated reference articles to Symfony 4Thisfixes#8642.-----I want to update these two files more deeply in a separate PR, so here their changes are minimal:* `reference/events.rst`* `reference/dic_tags.rst`-----Now, some questions:**1)** I've moved all custom Doctrine clases (custom DQL functions, custom DBAL types, custom database drivers, etc.) under `App\Bridge\Doctrine\` namespace (e.g. `Acme\HelloBundle\DQL\DatetimeFunction` -> `App\Bridge\Doctrine\DQL\DatetimeFunction`). I saw this in a Symfony app and I like it. Do you agree?**2)** I don't know how to update this section from `/reference/configuration/framework.rst`:```rstresources"""""""""**type**: ``string[]`` **default**: ``['FrameworkBundle:Form']``A list of all resources for form theming in PHP. This setting is not requiredif you're using the Twig format for your templates, in that case refer to:ref:`the form article <forms-theming-twig>`.Assume you have custom global form themes in``src/Resources/views/Form``, you can configure this like:.. configuration-block::    .. code-block:: yaml        # config/packages/framework.yaml        framework:            templating:                form:                    resources:                        - 'WebsiteBundle:Form'    [...].. note::    The default form templates from ``FrameworkBundle:Form`` will always    be included in the form resources... seealso::    See :ref:`forms-theming-global` for more information.```**3)** The `reference/configuration/doctrine.rst` contains A LOT of references to bundles, including options designed for bundles (`prefix`, `alias`, `is_bundle`) What should we do?* Remove all references to bundles, including those options?* Maintain all those options but update their explanations using the default Symfony Flex Recipe config? (seehttps://github.com/symfony/recipes/blob/db32040b48e9cf15299e7702a75a49e76999ff3f/doctrine/doctrine-bundle/1.6/config/packages/doctrine.yaml#L9-L15)* ...?Commits-------f709035 Restored the Assetic tags because they are removed in another PR206bf70 Updated Doctrine config reference about bundlese80995b Fixed PHP form theme resourcesef2a044 Remove App\Bridge\Doctrine\ namespaceda67105 Updated reference articles to Symfony 4

These aren't the defaults: they're the values that you get in yourconfig file from the recipe.

* 4.0: (36 commits)  Update event_listeners_subscribers.rst  Update event_listeners_subscribers.rst  [#8683] Tweaks based on feedback  [#8643] Removing default values  [#8734][#8736] Adding missing installation details  fixes thanks to the team!  add missing link target for Ansistrano  Restored the Assetic tags because they are removed in another PR  Corrected a spelling error.  Updated Doctrine config reference about bundles  Fixed PHP form theme resources  Remove App\Bridge\Doctrine\ namespace  Fixed the last references to security.yml  Updated the main security article  Updated security/* articles to Symfony 4  (WIP) Updated security/* articles to Symfony 4  Fixing build problems  tweaks thanks to@yceruto  updating the rest of the Doctrine docs  Update Custom UsernamePasswordToken Authenticator  ...