feature #5521 [Cookbook][WebServer] #5504 add a tip for the --force option (vincentaubert)

This PR was merged into the 2.8 branch.

Discussion
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[Cookbook][WebServer] #5504 add a tip for the --force option

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | 2.8
| Fixed tickets | #5504

Commits
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b88a17e [Cookbook][WebServer] #5504 add a tip for the --force option on server:start

Author: wouterj

cookbook/web_server/built_in.rst

@@ -39,6 +39,15 @@ can change the socket passing an IP address and a port as a command-line argumen
 
     $ php app/console server:run 192.168.0.1:8080
 
+.. note::
+
+    You can use the ``--force`` option to force the web server start
+    if the process wasn't correctly stopped (without using the ``server:stop`` command).
+
+    .. code-block:: bash
+
+        $ php app/console server:start --force
+
 .. note::
 
     You can use the ``server:status`` command to check if a web server is