docs: update some outdated namespaces in example code (#1747)

Author: thoresuenert

docs/1-essentials/02-views.md

@@ -502,7 +502,7 @@ This component provides a form element that will post by default and includes th
 
 ```html
 <?php
-use function \Tempest\uri;
+use function \Tempest\Router\uri;
 ?>
 
 <x-form :action="uri(StorePostController::class)">

docs/4-internals/03-view-spec.md

@@ -473,7 +473,7 @@ This component provides a form element that will post by default and includes th
 
 ```html
 <?php
-use function \Tempest\uri;
+use function \Tempest\Router\uri;
 ?>
 
 <x-form :action="uri(StorePostController::class)">