skip tests that requires gmp ext if not enabled (#44727)

Author: imdhemy

tests/Integration/Database/EloquentModelCustomCastingTest.php

@@ -59,7 +59,7 @@ protected function tearDown(): void
     }
 
     /**
-     * Tests...
+     * @requires extension gmp
      */
     public function testSavingCastedAttributesToDatabase()
     {
@@ -97,6 +97,9 @@ public function testSavingCastedAttributesToDatabase()
         $this->assertInstanceOf(GMP::class, $model->amount);
     }
 
+    /**
+     * @requires extension gmp
+     */
     public function testInvalidArgumentExceptionOnInvalidValue()
     {
         /** @var \Illuminate\Tests\Integration\Database\CustomCasts $model */
@@ -115,6 +118,9 @@ public function testInvalidArgumentExceptionOnInvalidValue()
         $this->assertSame('address_line_two_value', $model->address->lineTwo);
     }
 
+    /**
+     * @requires extension gmp
+     */
     public function testInvalidArgumentExceptionOnNull()
     {
         /** @var \Illuminate\Tests\Integration\Database\CustomCasts $model */
@@ -133,6 +139,9 @@ public function testInvalidArgumentExceptionOnNull()
         $this->assertSame('address_line_two_value', $model->address->lineTwo);
     }
 
+    /**
+     * @requires extension gmp
+     */
     public function testModelsWithCustomCastsCanBeConvertedToArrays()
     {
         /** @var \Illuminate\Tests\Integration\Database\CustomCasts $model */