feature #39948 [Notifier] [SpotHit] Add the bridge (JamesHemery)

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

Discussion
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[Notifier] [SpotHit] Add the bridge

| Q             | A
| ------------- | ---
| Branch?       | 5.x
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| License       | MIT
| Doc PR        | symfony/symfony-docs#14869
| Recipe PR        | symfony/recipes#881

@OskarStark Bridge added :)

Commits
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afcca88af2 [Notifier] [SpotHit] Add the bridge

Author: OskarStark

Exception/UnsupportedSchemeException.php

@@ -68,6 +68,10 @@ class UnsupportedSchemeException extends LogicException
             'class' => Bridge\FreeMobile\FreeMobileTransportFactory::class,
             'package' => 'symfony/free-mobile-notifier',
         ],
+        'spothit' => [
+            'class' => Bridge\SpotHit\SpotHitTransportFactory::class,
+            'package' => 'symfony/spothit-notifier',
+        ],
         'ovhcloud' => [
             'class' => Bridge\OvhCloud\OvhCloudTransportFactory::class,
             'package' => 'symfony/ovh-cloud-notifier',