Add issue number

Author: compulim

CHANGELOG.md

@@ -84,7 +84,7 @@ Notes: web developers are advised to use [`~` (tilde range)](https://github.com/
    - Set `styleOptions.speechRecognitionContinuous` to `true` with a Web Speech API provider with continuous mode support
 - Added support of [contentless activity in livestream](https://github.com/microsoft/BotFramework-WebChat/blob/main/docs/LIVESTREAMING.md#scenario-3-interim-activities-with-no-content), in PR [#5430](https://github.com/microsoft/BotFramework-WebChat/pull/5430), by [@compulim](https://github.com/compulim)
 - Added sliding dots typing indicator in Fluent theme, in PR [#5447](https://github.com/microsoft/BotFramework-WebChat/pull/5447) and PR [#5448](https://github.com/microsoft/BotFramework-WebChat/pull/5448), by [@compulim](https://github.com/compulim)
-- Added attachment preview for `sendAttachmentOn: "send"`, in PR [#XXX](https://github.com/microsoft/BotFramework-WebChat/pull/XXX), by [@compulim](https://github.com/compulim)
+- Resolved [#5463](https://github.com/microsoft/BotFramework-WebChat/issues/5463). Added attachment preview for `sendAttachmentOn: "send"`, in PR [#XXX](https://github.com/microsoft/BotFramework-WebChat/pull/XXX), by [@compulim](https://github.com/compulim)
    - Attaching files will no longer remove previously attached files
 
 ### Changed