Add in the DOW crawler documentation code sample to show how to tick checkboxes

Author: LucileDT

components/dom_crawler.rst

@@ -482,6 +482,9 @@ To work with multi-dimensional fields::
         <input name="multi[]"/>
         <input name="multi[]"/>
         <input name="multi[dimensional]"/>
+        <input name="multi[dimensional][]" value="1"/>
+        <input name="multi[dimensional][]" value="2"/>
+        <input name="multi[dimensional][]" value="3"/>
     </form>
 
 Pass an array of values::
@@ -495,6 +498,11 @@ Pass an array of values::
         'dimensional' => 'an other value',
     ]]);
 
+    // tick multiple checkboxes at once
+    $form->setValues(['multi' => [
+        'dimensional' => [1, 3] // it uses the input value to determine which checkbox to tick
+    ]]);
+
 This is great, but it gets better! The ``Form`` object allows you to interact
 with your form like a browser, selecting radio values, ticking checkboxes,
 and uploading files::