minor #3350 Fix doc example (jenyak)

This PR was squashed before being merged into the 3.0.x-dev branch.

Discussion
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Fix doc example

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Commits
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e69fbca Fix doc example

doc/design.rst

@@ -206,7 +206,7 @@ Finally, add this custom theme to the list of themes used to render backend form
 
                 // don't forget to add EasyAdmin's form theme at the end of the list
                 // (otherwise you'll lose all the styles for the rest of form fields)
-                ->formThemes(['admin/form.html.twig', '@EasyAdmin/crud/form_theme.html.twig']);
+                ->setFormThemes(['admin/form.html.twig', '@EasyAdmin/crud/form_theme.html.twig'])
             ;
         }
     }
@@ -235,7 +235,7 @@ the :doc:`CRUD controllers </crud>` to add your own CSS and JavaScript files::
                 // and JS assets are added just before the closing </body> element
                 ->addCssFile('build/admin.css')
                 ->addCssFile('https://example.org/css/admin2.css')
-                ->addJsFile('build/admin.js');
+                ->addJsFile('build/admin.js')
                 ->addJsFile('https://example.org/js/admin2.js')
 
                 // use these generic methods to add any code before </head> or </body>

doc/fields.rst

@@ -67,7 +67,7 @@ creates fields automatically for them and applies the default config options::
 EasyAdmin transforms these generic ``Field`` objects into the specific objects
 used to display each type of property::
 
-    use EasyCorp\Bundle\EasyAdminBundle\Field;
+    use EasyCorp\Bundle\EasyAdminBundle\Field\Field;
 
     public function configureFields(string $pageName): iterable
     {
@@ -82,11 +82,11 @@ used to display each type of property::
 
 **Option 3.** Return the appropriate field objects to display each property::
 
-    use EasyCorp\Bundle\EasyAdminBundle\TextField;
-    use EasyCorp\Bundle\EasyAdminBundle\TextEditorField;
-    use EasyCorp\Bundle\EasyAdminBundle\MoneyField;
-    use EasyCorp\Bundle\EasyAdminBundle\IntegerField;
-    use EasyCorp\Bundle\EasyAdminBundle\DateTimeField;
+    use EasyCorp\Bundle\EasyAdminBundle\Field\TextField;
+    use EasyCorp\Bundle\EasyAdminBundle\Field\TextEditorField;
+    use EasyCorp\Bundle\EasyAdminBundle\Field\MoneyField;
+    use EasyCorp\Bundle\EasyAdminBundle\Field\IntegerField;
+    use EasyCorp\Bundle\EasyAdminBundle\Field\DateTimeField;
 
     public function configureFields(string $pageName): iterable
     {