[Mime] Add TemplatedEmail::$locale to the serialized props

Author: mkrauser

Mime/TemplatedEmail.php

@@ -100,7 +100,7 @@ public function markAsRendered(): void
      */
     public function __serialize(): array
     {
-        return [$this->htmlTemplate, $this->textTemplate, $this->context, parent::__serialize()];
+        return [$this->htmlTemplate, $this->textTemplate, $this->context, parent::__serialize(),  $this->locale];
     }
 
     /**
@@ -109,6 +109,7 @@ public function __serialize(): array
     public function __unserialize(array $data): void
     {
         [$this->htmlTemplate, $this->textTemplate, $this->context, $parentData] = $data;
+        $this->locale = $data[4] ?? null;
 
         parent::__unserialize($parentData);
     }

Tests/Mime/TemplatedEmailTest.php

@@ -43,12 +43,14 @@ public function testSerialize()
             ->textTemplate('text.txt.twig')
             ->htmlTemplate('text.html.twig')
             ->context($context = ['a' => 'b'])
+            ->locale($locale = 'fr_FR')
         ;
 
         $email = unserialize(serialize($email));
         $this->assertEquals('text.txt.twig', $email->getTextTemplate());
         $this->assertEquals('text.html.twig', $email->getHtmlTemplate());
         $this->assertEquals($context, $email->getContext());
+        $this->assertEquals($locale, $email->getLocale());
     }
 
     public function testSymfonySerialize()