Add support for sending raw (non-encoded) attachments in Resend mail (#55837)

* Add support for sending raw (non-encoded) attachments in Resend mail driver

* Style fix

Author: Roywcm

src/Illuminate/Mail/Transport/ResendTransport.php

@@ -72,12 +72,19 @@ protected function doSend(SentMessage $message): void
         if ($email->getAttachments()) {
             foreach ($email->getAttachments() as $attachment) {
                 $attachmentHeaders = $attachment->getPreparedHeaders();
+                $contentType = $attachmentHeaders->get('Content-Type')->getBody();
 
                 $filename = $attachmentHeaders->getHeaderParameter('Content-Disposition', 'filename');
 
+                if ($contentType == 'text/calendar') {
+                    $content = $attachment->getBody();
+                } else {
+                    $content = str_replace("\r\n", '', $attachment->bodyToString());
+                }
+
                 $item = [
-                    'content_type' => $attachmentHeaders->get('Content-Type')->getBody(),
-                    'content' => str_replace("\r\n", '', $attachment->bodyToString()),
+                    'content_type' => $contentType,
+                    'content' => $content,
                     'filename' => $filename,
                 ];