minor #20539 [Notifier] Update notifier.rst (ikerib)

This PR was merged into the 7.3 branch.

Discussion
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[Notifier] Update notifier.rst

Brevo third-party service now supports webhooks.

Related issue #20514

Commits
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d1400d4 Update notifier.rst

Author: javiereguiluz

notifier.rst

@@ -76,7 +76,7 @@ Service
                     **Webhook support**: No
 `Brevo`_            **Install**: ``composer require symfony/brevo-notifier`` \
                     **DSN**: ``brevo://API_KEY@default?sender=SENDER`` \
-                    **Webhook support**: No
+                    **Webhook support**: Yes
 `Clickatell`_       **Install**: ``composer require symfony/clickatell-notifier`` \
                     **DSN**: ``clickatell://ACCESS_TOKEN@default?from=FROM`` \
                     **Webhook support**: No