Add mentionedMessageTemplate field when sending or receiving a message

[Problem/Question]
In the current Sendbird Flutter SDK, mentionedMessageTemplate is not included when sending and receiving a message.

Due to the issue above, profanity filtered message with mentioned users cannot be received. I tried with the normal message from the API, it does include the profanity filtered message but not with the mentioned users.


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[SDK Version]

Flutter 3.13.6 • channel stable • GitHub - flutter/flutter: Flutter makes it easy and fast to build beautiful apps for mobile and beyond
Framework • revision ead455963c (3 months ago) • 2023-09-26 18:28:17 -0700
Engine • revision a794cf2681
Tools • Dart 3.1.3 • DevTools 2.25.0

SDK: sendbird_chat_sdk 4.1.2

[Reproduction Steps]

Send or Receive a message

[Frequency]
Always

[Current impact]

Profanity filtered message with mentioned users cannot be received.

The initial PR has been closed in the SDK github.