feature #44303 Add Engagespot bridge (danut007ro)

This PR was squashed before being merged into the 6.1 branch.

Discussion
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Add Engagespot bridge

| Q             | A
| ------------- | ---
| Branch?       | 6.1
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Tickets       | no ticket
| License       | MIT
| Doc PR        | symfony/symfony-docs#16165

Add [Engagespot](https://engagespot.co/) integration for push notifications.

Commits
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c7e1d1a78e Add Engagespot bridge

Author: fabpot

Exception/UnsupportedSchemeException.php

@@ -32,6 +32,10 @@ class UnsupportedSchemeException extends LogicException
             'class' => Bridge\Discord\DiscordTransportFactory::class,
             'package' => 'symfony/discord-notifier',
         ],
+        'engagespot' => [
+            'class' => Bridge\Engagespot\EngagespotTransportFactory::class,
+            'package' => 'symfony/engagespot-notifier',
+        ],
         'esendex' => [
             'class' => Bridge\Esendex\EsendexTransportFactory::class,
             'package' => 'symfony/esendex-notifier',

Transport.php

@@ -15,6 +15,7 @@
 use Symfony\Component\Notifier\Bridge\AmazonSns\AmazonSnsTransportFactory;
 use Symfony\Component\Notifier\Bridge\Clickatell\ClickatellTransportFactory;
 use Symfony\Component\Notifier\Bridge\Discord\DiscordTransportFactory;
+use Symfony\Component\Notifier\Bridge\Engagespot\EngagespotTransportFactory;
 use Symfony\Component\Notifier\Bridge\Esendex\EsendexTransportFactory;
 use Symfony\Component\Notifier\Bridge\Expo\ExpoTransportFactory;
 use Symfony\Component\Notifier\Bridge\Firebase\FirebaseTransportFactory;
@@ -71,6 +72,7 @@ final class Transport
         AmazonSnsTransportFactory::class,
         ClickatellTransportFactory::class,
         DiscordTransportFactory::class,
+        EngagespotTransportFactory::class,
         EsendexTransportFactory::class,
         ExpoTransportFactory::class,
         FirebaseTransportFactory::class,