[Notifier] Add gatewayapi-notifier

Author: PGLongo

notifier.rst

@@ -58,6 +58,7 @@ Service     Package                           DSN
 ==========  ================================  ====================================================
 Esendex     ``symfony/esendex-notifier``      ``esendex://USER_NAME:PASSWORD@default?accountreference=ACCOUNT_REFERENCE&from=FROM``
 FreeMobile  ``symfony/free-mobile-notifier``  ``freemobile://LOGIN:PASSWORD@default?phone=PHONE``
+GatewayApi  ``symfony/gatewayapi-notifier``   ``gatewayapi://TOKEN@default?from=FROM``
 Infobip     ``symfony/infobip-notifier``      ``infobip://ACCESS_TOKEN@HOST?from=FROM``
 Iqsms       ``symfony/iqsms-notifier``        ``iqsms://LOGIN:PASSWORD@default?from=FROM``
 Mobyt       ``symfony/mobyt-notifier``        ``mobyt://USER_KEY:ACCESS_TOKEN@default?from=FROM``
@@ -80,7 +81,7 @@ Twilio      ``symfony/twilio-notifier``       ``twilio://SID:TOKEN@default?from=
 
 .. versionadded:: 5.3
 
-    The Iqsms and Octopush integrations were introduced in Symfony 5.3.
+    The Iqsms, GatewayApi and Octopush integrations were introduced in Symfony 5.3.
 
 To enable a texter, add the correct DSN in your ``.env`` file and
 configure the ``texter_transports``: