Update Mpdf (Php8.5 compatibility) r390 (#4595)

Author: oleibman

composer.lock

@@ -44,8 +44,6 @@ public function xtestAddColor(array $testColors, array $expectedResult): void
         $workbookReflection = new ReflectionClass(Workbook::class);
         $methodAddColor = $workbookReflection->getMethod('addColor');
         $propertyPalette = $workbookReflection->getProperty('palette');
-        $methodAddColor->setAccessible(true);
-        $propertyPalette->setAccessible(true);
 
         foreach ($testColors as $testColor) {
             $methodAddColor->invoke($this->workbook, $testColor);
@@ -73,7 +71,6 @@ public function arrayAddColor(): array
 
         $workbookReflection = new ReflectionClass(Workbook::class);
         $propertyPalette = $workbookReflection->getProperty('palette');
-        $propertyPalette->setAccessible(true);
 
         $palette = $propertyPalette->getValue($this->workbook);
         self::assertIsArray($palette);