[9.x]: Add mergeUnless to resource ConditionallyLoadsAttributes t…

…rait (laravel#43567)

* [9.x]: Add mergeUnless to resource ConditionallyLoadsAttributesTrait

* Update Queueable.php

* Update ConditionallyLoadsAttributes.php

Co-authored-by: Taylor Otwell <taylor@laravel.com>

src/Illuminate/Http/Resources/ConditionallyLoadsAttributes.php

@@ -121,7 +121,7 @@ protected function merge($value)
     }
 
     /**
-     * Merge a value based on a given condition.
+     * Merge a value if the given condition is truthy.
      *
      * @param  bool  $condition
      * @param  mixed  $value
@@ -132,6 +132,18 @@ protected function mergeWhen($condition, $value)
         return $condition ? new MergeValue(value($value)) : new MissingValue;
     }
 
+    /**
+     * Merge a value unless the given condition is truthy.
+     *
+     * @param  bool  $condition
+     * @param  mixed  $value
+     * @return \Illuminate\Http\Resources\MergeValue|mixed
+     */
+    protected function mergeUnless($condition, $value)
+    {
+        return ! $condition ? new MergeValue(value($value)) : new MissingValue;
+    }
+
     /**
      * Merge the given attributes.
      *