feature #11333 [Routing] Invokable route loader services (fancyweb)

This PR was merged into the master branch.

Discussion
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[Routing] Invokable route loader services

#eufossa

doc for symfony/symfony#30933

Also the notation with one column has been deprecated so I updated this part as well.

Commits
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d9b4121 [Routing] Invokable route loader services

routing/custom_route_loader.rst

@@ -133,6 +133,15 @@ extend or implement any special class, but the called method must return a
     cached by the framework. So whenever your service should load new routes,
     don't forget to clear the cache.
 
+.. tip::
+
+    If your service is invokable, you don't need to precise the method to use.
+
+.. versionadded:: 4.3
+
+    The support of the ``__invoke()`` method to create invokable route loader
+    services was introduced in Symfony 4.3.
+
 Creating a custom Loader
 ------------------------