bug #35172 [Mailer][MailchimpBridge] Fix incorrect sender address when sender has name (vilius-g)

This PR was merged into the 4.3 branch.

Discussion
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[Mailer][MailchimpBridge] Fix incorrect sender address when sender has name

| Q             | A
| ------------- | ---
| Branch?       | 4.3
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Tickets       |
| License       | MIT
| Doc PR        |

This fixes the same problem as https://github.com/symfony/symfony/commit/6dbac13a07c23f321b04489b6a9773 but for HTTP transport.

I am also not sure that `from_email` parameter is needed here at all as it is optional for this API call.

Commits
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9e12a6dcda [Mailer][MailchimpBridge] Fix incorrect sender address when sender has name

src/Symfony/Component/Mailer/Bridge/Mailchimp/Http/MandrillTransport.php

@@ -42,7 +42,7 @@ class MandrillTransport extends AbstractHttpTransport
             'json' => [
                 'key' => $this->key,
                 'to' => $this->stringifyAddresses($envelope->getRecipients()),
-                'from_email' => $envelope->getSender()->toString(),
+                'from_email' => $envelope->getSender()->getAddress(),
                 'raw_message' => $message->toString(),
             ],
         ]);