feature #51014 [Mailer] Add Scaleway bridge (MrMicky-FR)

This PR was squashed before being merged into the 6.4 branch.

Discussion
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[Mailer] Add Scaleway bridge

| Q             | A
| ------------- | ---
| Branch?       | 6.4
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| License       | MIT
| Doc PR        | symfony/symfony-docs#18581

This PR adds a new mailer bridge for [Scaleway Transactional Emails](https://www.scaleway.com/en/transactional-email-tem/).

I've been using this bridge in production for several months, with thousands of emails sent, and everything works perfectly 🚀

Commits
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bd9922622f [Mailer] Add Scaleway bridge

Author: fabpot

Exception/UnsupportedSchemeException.php

@@ -56,6 +56,10 @@ class UnsupportedSchemeException extends LogicException
             'class' => Bridge\Postmark\Transport\PostmarkTransportFactory::class,
             'package' => 'symfony/postmark-mailer',
         ],
+        'scaleway' => [
+            'class' => Bridge\Scaleway\Transport\ScalewayTransportFactory::class,
+            'package' => 'symfony/scaleway-mailer',
+        ],
         'sendgrid' => [
             'class' => Bridge\Sendgrid\Transport\SendgridTransportFactory::class,
             'package' => 'symfony/sendgrid-mailer',

Tests/Exception/UnsupportedSchemeExceptionTest.php

@@ -23,6 +23,7 @@
 use Symfony\Component\Mailer\Bridge\Mailjet\Transport\MailjetTransportFactory;
 use Symfony\Component\Mailer\Bridge\OhMySmtp\Transport\OhMySmtpTransportFactory;
 use Symfony\Component\Mailer\Bridge\Postmark\Transport\PostmarkTransportFactory;
+use Symfony\Component\Mailer\Bridge\Scaleway\Transport\ScalewayTransportFactory;
 use Symfony\Component\Mailer\Bridge\Sendgrid\Transport\SendgridTransportFactory;
 use Symfony\Component\Mailer\Bridge\Sendinblue\Transport\SendinblueTransportFactory;
 use Symfony\Component\Mailer\Exception\UnsupportedSchemeException;
@@ -46,6 +47,7 @@ public static function setUpBeforeClass(): void
             MandrillTransportFactory::class => false,
             OhMySmtpTransportFactory::class => false,
             PostmarkTransportFactory::class => false,
+            ScalewayTransportFactory::class => false,
             SendgridTransportFactory::class => false,
             SendinblueTransportFactory::class => false,
             SesTransportFactory::class => false,
@@ -76,6 +78,7 @@ public static function messageWhereSchemeIsPartOfSchemeToPackageMapProvider(): \
         yield ['mandrill', 'symfony/mailchimp-mailer'];
         yield ['ohmysmtp', 'symfony/oh-my-smtp-mailer'];
         yield ['postmark', 'symfony/postmark-mailer'];
+        yield ['scaleway', 'symfony/scaleway-mailer'];
         yield ['sendgrid', 'symfony/sendgrid-mailer'];
         yield ['sendinblue', 'symfony/sendinblue-mailer'];
         yield ['ses', 'symfony/amazon-mailer'];

Transport.php

@@ -23,6 +23,7 @@
 use Symfony\Component\Mailer\Bridge\Mailjet\Transport\MailjetTransportFactory;
 use Symfony\Component\Mailer\Bridge\OhMySmtp\Transport\OhMySmtpTransportFactory;
 use Symfony\Component\Mailer\Bridge\Postmark\Transport\PostmarkTransportFactory;
+use Symfony\Component\Mailer\Bridge\Scaleway\Transport\ScalewayTransportFactory;
 use Symfony\Component\Mailer\Bridge\Sendgrid\Transport\SendgridTransportFactory;
 use Symfony\Component\Mailer\Bridge\Sendinblue\Transport\SendinblueTransportFactory;
 use Symfony\Component\Mailer\Exception\InvalidArgumentException;
@@ -55,6 +56,7 @@ final class Transport
         MandrillTransportFactory::class,
         OhMySmtpTransportFactory::class,
         PostmarkTransportFactory::class,
+        ScalewayTransportFactory::class,
         SendgridTransportFactory::class,
         SendinblueTransportFactory::class,
         SesTransportFactory::class,