feature #40646 [Notifier] Add MessageBird notifier bridge (StaffNowa)

This PR was squashed before being merged into the 5.3-dev branch.

Discussion
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[Notifier] Add MessageBird notifier bridge

| Q             | A
| ------------- | ---
| Branch?       | 5.x
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| License       | MIT
| Doc PR        | symfony/symfony-docs#15180
| Recipe PR   | symfony/recipes/pull/922

MessageBird notifier https://developers.messagebird.com/docs/conversations/send-messages-curl/

Commits
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761817ed81 [Notifier] Add MessageBird notifier bridge

Author: OskarStark

Resources/config/notifier_transports.php

@@ -28,6 +28,7 @@
 use Symfony\Component\Notifier\Bridge\LinkedIn\LinkedInTransportFactory;
 use Symfony\Component\Notifier\Bridge\Mattermost\MattermostTransportFactory;
 use Symfony\Component\Notifier\Bridge\Mercure\MercureTransportFactory;
+use Symfony\Component\Notifier\Bridge\MessageBird\MessageBirdTransportFactory;
 use Symfony\Component\Notifier\Bridge\MicrosoftTeams\MicrosoftTeamsTransportFactory;
 use Symfony\Component\Notifier\Bridge\Mobyt\MobytTransportFactory;
 use Symfony\Component\Notifier\Bridge\Nexmo\NexmoTransportFactory;
@@ -184,5 +185,9 @@
         ->set('notifier.transport_factory.smsbiuras', SmsBiurasTransportFactory::class)
             ->parent('notifier.transport_factory.abstract')
             ->tag('texter.transport_factory')
+
+        ->set('notifier.transport_factory.messagebird', MessageBirdTransportFactory::class)
+            ->parent('notifier.transport_factory.abstract')
+            ->tag('texter.transport_factory')
     ;
 };