[Notifier]: add Ntfy bridge and links to push bridges' README

Author: mikaelkael

notifier.rst

@@ -423,11 +423,12 @@ integration with these push services:
 =================  ====================================  =================================================================================
 Service            Package                               DSN
 =================  ====================================  =================================================================================
-`Engagespot`_      ``symfony/engagespot-notifier``        ``engagespot://API_KEY@default?campaign_name=CAMPAIGN_NAME``
-`Expo`_            ``symfony/expo-notifier``              ``expo://Token@default``
-`OneSignal`_       ``symfony/one-signal-notifier``        ``onesignal://APP_ID:API_KEY@default?defaultRecipientId=DEFAULT_RECIPIENT_ID``
-`PagerDuty`_       ``symfony/pager-duty-notifier``        ``pagerduty://TOKEN@SUBDOMAIN``
-`Pushover`_        ``symfony/pushover-notifier``          ``pushover://USER_KEY:APP_TOKEN@default``
+`Engagespot`_      ``symfony/engagespot-notifier``       ``engagespot://API_KEY@default?campaign_name=CAMPAIGN_NAME``
+`Expo`_            ``symfony/expo-notifier``             ``expo://Token@default``
+`OneSignal`_       ``symfony/one-signal-notifier``       ``onesignal://APP_ID:API_KEY@default?defaultRecipientId=DEFAULT_RECIPIENT_ID``
+`Ntfy`_            ``symfony/ntfy-notifier``             ``ntfy://default/topic_name``
+`PagerDuty`_       ``symfony/pager-duty-notifier``       ``pagerduty://TOKEN@SUBDOMAIN``
+`Pushover`_        ``symfony/pushover-notifier``         ``pushover://USER_KEY:APP_TOKEN@default``
 =================  ====================================  =================================================================================
 
 .. versionadded:: 6.1
@@ -998,6 +999,7 @@ is dispatched. Listeners receive a
 .. _`MicrosoftTeams`: https://github.com/symfony/symfony/blob/{version}/src/Symfony/Component/Notifier/Bridge/MicrosoftTeams/README.md
 .. _`Mobyt`: https://github.com/symfony/symfony/blob/{version}/src/Symfony/Component/Notifier/Bridge/Mobyt/README.md
 .. _`Nexmo`: https://github.com/symfony/symfony/blob/{version}/src/Symfony/Component/Notifier/Bridge/Nexmo/README.md
+.. _`Ntfy`: https://github.com/symfony/symfony/blob/{version}/src/Symfony/Component/Notifier/Bridge/Ntfy/README.md
 .. _`Octopush`: https://github.com/symfony/symfony/blob/{version}/src/Symfony/Component/Notifier/Bridge/Octopush/README.md
 .. _`OneSignal`: https://github.com/symfony/symfony/blob/{version}/src/Symfony/Component/Notifier/Bridge/OneSignal/README.md
 .. _`OrangeSms`: https://github.com/symfony/symfony/blob/{version}/src/Symfony/Component/Notifier/Bridge/OrangeSms/README.md