fix: Multiple edited message shows up as a new message on recipient devices

[Sahil-Mandal15]

Fixes #14906

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This PR fixes the issue #14906 which mentions that whenever we edit a message twice while the device is not connected to the internet, then after connecting to the internet, the final edited message creates a new message.

While debugging, I found out that when a message is edited, the app tried to search for the parent of that particular message and this particular helper function returned the most previous version/parent of the message and not the root message, which caused the new update request (after connection is restored) to be a fresh creation instead of edit (as this request was made using the most recent version which was not available in the server and hence it is treated as a new message).

The fix was simple, I just changed the logic to fetch the root parent instead of the most recent version of the second edited message.