Revert "fix: fixed back button causing issues when using default ht…

…ml validation"

This reverts commit a29da8c.

packages/plugin/src/Bundles/Form/Context/Pages/PageContext.php

@@ -6,6 +6,7 @@
 use Solspace\Freeform\Events\Forms\HandleRequestEvent;
 use Solspace\Freeform\Events\Forms\ResetEvent;
 use Solspace\Freeform\Events\Forms\ValidationEvent;
+use Solspace\Freeform\Fields\SubmitField;
 use Solspace\Freeform\Form\Bags\PropertyBag;
 use Solspace\Freeform\Freeform;
 use Solspace\Freeform\Library\Composer\Components\Form;
@@ -14,8 +15,6 @@
 
 class PageContext
 {
-    public const KEY_ACTION_BACK = 'back';
-
     public function __construct()
     {
         Event::on(Form::class, Form::EVENT_BEFORE_VALIDATE, [$this, 'onValidate']);
@@ -42,7 +41,7 @@ public function handleNavigateBack(HandleRequestEvent $event)
             return;
         }
 
-        $shouldWalkBack = self::KEY_ACTION_BACK === RequestHelper::post(Form::ACTION_KEY);
+        $shouldWalkBack = null !== RequestHelper::post(SubmitField::PREVIOUS_PAGE_INPUT_NAME);
         if ($shouldWalkBack) {
             $pageHistory = $bag->get(Form::PROPERTY_PAGE_HISTORY, []);
             $index = array_pop($pageHistory) ?? 0;