[MXEvent] Handle `m.relates_to` move from event encrypted content to clear content when decrypting an event.
[MXEvent] Handle `m.relates_to` move from event encrypted content to clear content when decrypting an event.

matrix-org/matrix-ios-sdk,matrix-org/matrix-ios-sdk,matrix-org/matrix-ios-sdk,matrix-org/matrix-ios-sdk,matrix-org/matrix-ios-sdk