Fix a coding standard issue

MauricioFauth · MauricioFauth · commit 6cc701e113e9 · 2022-11-06T18:06:32.000-03:00
Signed-off-by: Maurício Meneghini Fauth &lt;mauricio@fauth.dev&gt;
diff --git a/test/classes/SystemDatabaseTest.php b/test/classes/SystemDatabaseTest.php
@@ -45,7 +45,7 @@ protected function setUp(): void
 
         $dbi->expects($this->any())
             ->method('quoteString')
-            ->will($this->returnCallback(function (string $string) {
+            ->will($this->returnCallback(static function (string $string) {
                 return "'" . $string . "'";
             }));
 
