[Notifier] Document sinch bridge dsn

Author: jschaedl

notifier.rst

@@ -55,6 +55,7 @@ Service   Package                        DSN
 Twilio    ``symfony/twilio-notifier``    ``twilio://SID:TOKEN@default?from=FROM``
 Nexmo     ``symfony/nexmo-notifier``     ``nexmo://KEY:SECRET@default?from=FROM``
 OvhCloud  ``symfony/ovhcloud-notifier``  ``ovhcloud://KEY:SECRET@default?from=FROM``
+Sinch     ``symfony/sinch-notifier``     ``sinch://ACCOUNT_ID:AUTH_TOKEN@default?from=FROM``
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 .. versionadded:: 5.1