fix: unable to save an edited page (#62)

Author: imorland

src/Api/Resource/PageResource.php

@@ -95,7 +95,7 @@ public function fields(): array
 
             Schema\Str::make('slug')
                 ->requiredOnCreate()
-                ->unique('pages', 'slug')
+                ->unique('pages', 'slug', true)
                 ->maxLength(200)
                 ->writable(),