minor #11377 Switch the prefered local web server to the Symfony one (fabpot)

This PR was submitted for the 4.2 branch but it was merged into the 3.4 branch instead (closes #11377).

Discussion
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Switch the prefered local web server to the Symfony one

I'm targeting 4.2 instead of 3.4 as the Symfony web server PR (#11207) was merged into 4.2 for a reason I don't understand.

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Commits
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ff8b8bf switched the prefered local web server to the Symfony one

Author: javiereguiluz

frontend/encore/dev-server.rst

@@ -26,12 +26,6 @@ by the normal `webpack-dev-server`_. For example:
 
 This will start a server at ``https://localhost:9000``.
 
-.. note::
-
-    This Webpack server is independent from
-    :doc:`Symfony's development web server </setup/built_in_web_server>` and
-    you need to run both separately.
-
 Using dev-server inside a VM
 ----------------------------
 

setup/built_in_web_server.rst

@@ -4,11 +4,15 @@
 How to Use PHP's built-in Web Server
 ====================================
 
-Since PHP 5.4 the CLI SAPI comes with a `built-in web server`_. It can be used
-to run your PHP applications locally during development, for testing or for
-application demonstrations. This way, you don't have to bother configuring
-a full-featured web server such as
-:doc:`Apache or Nginx </setup/web_server_configuration>`.
+The PHP CLI SAPI comes with a `built-in web server`_. It can be used to run your
+PHP applications locally during development, for testing or for application
+demonstrations. This way, you don't have to bother configuring a full-featured
+web server such as :doc:`Apache or Nginx </setup/web_server_configuration>`.
+
+.. tip::
+
+    The preferred way to develop your Symfony application is to use
+    :doc:`Symfony Local Web Server </setup/symfony_server>`.
 
 .. caution::
 

setup/web_server_configuration.rst

@@ -5,10 +5,11 @@ Configuring a Web Server
 ========================
 
 The preferred way to develop your Symfony application is to use
-:doc:`PHP's internal web server </setup/built_in_web_server>`. However,
-when using an older PHP version or when running the application in the production
-environment, you'll need to use a fully-featured web server. This article
-describes several ways to use Symfony with Apache or Nginx.
+:doc:`Symfony Local Web Server </setup/symfony_server>`.
+
+However, when running the application in the production environment, you'll need
+to use a fully-featured web server. This article describes several ways to use
+Symfony with Apache or Nginx.
 
 When using Apache, you can configure PHP as an
 :ref:`Apache module <web-server-apache-mod-php>` or with FastCGI using