bug symfony#53243 [Mailer][Postmark] Add missing changelog for webhook support (OskarStark)

This PR was merged into the 6.3 branch.

Discussion
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[Mailer][Postmark] Add missing changelog for webhook support

| Q             | A
| ------------- | ---
| Branch?       | 6.3
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        | --
| License       | MIT

Commits
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ee4b242 [Mailer][Postmark] Add missing changelog for webhook support

Author: fabpot

src/Symfony/Component/Mailer/Bridge/Postmark/CHANGELOG.md

@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+6.3
+---
+
+ * Add support for webhooks
+
 4.4.0
 -----