minor #14651 Added config reference for router.default_uri (Nyholm)

This PR was squashed before being merged into the 5.1 branch.

Discussion
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Added config reference for router.default_uri

This was missing. It is a super great feature =)

Commits
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e60cd0e Added config reference for router.default_uri

Author: javiereguiluz

reference/configuration/framework.rst

@@ -190,6 +190,7 @@ Configuration
 
 * `router`_
 
+  * `default_uri`_
   * `http_port`_
   * `https_port`_
   * `resource`_
@@ -1145,6 +1146,14 @@ The type of the resource to hint the loaders about the format. This isn't
 needed when you use the default routers with the expected file extensions
 (``.xml``, ``.yaml``, ``.php``).
 
+default_uri
+...........
+
+**type**: ``string``
+
+The default URI used to generate URLs in a non-HTTP context (see
+:ref:`Generating URLs in Commands <router-generate-urls-commands>`).
+
 http_port
 .........
 

routing.rst

@@ -2055,6 +2055,8 @@ If you need to generate URLs dynamically or if you are using pure JavaScript
 code, this solution doesn't work. In those cases, consider using the
 `FOSJsRoutingBundle`_.
 
+.. _router-generate-urls-commands:
+
 Generating URLs in Commands
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~