Changelog update

Author: rleojoseph

CHANGELOG.md

@@ -7,6 +7,7 @@
 - **Feature:** Updated create method with optional `fromCache` variable that helps to load the mini-app from cache.
 `MiniApp#create(appId:versionId:queryParams:completionHandler:messageInterface:adsDisplayer:fromCache)`
 `MiniApp#create(appInfo:queryParams:completionHandler:messageInterface:adsDisplayer:fromCache)`
+- **Feature:** Added a new interface `downloadFile(fileName:url:headers:completionHandler:)` in `MiniAppMessageDelegate` to support downloadFile behavior with custom file.
 
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 ### 4.0.0  (2022-03-01)