Prevent multiple conversion of the same voice message audio file. (#1887)

ElementX/Sources/Services/Session/UserSessionProtocol.swift

@@ -30,6 +30,7 @@ protocol UserSessionProtocol {
     
     var clientProxy: ClientProxyProtocol { get }
     var mediaProvider: MediaProviderProtocol { get }
+    var voiceMessageMediaManager: VoiceMessageMediaManagerProtocol { get }
     
     var sessionVerificationController: SessionVerificationControllerProxyProtocol? { get }