refactor: make linter happy

app/src/main/java/com/bitcointxoko/gudariwallet/service/WalletNotificationService.kt

@@ -30,6 +30,7 @@ import okhttp3.Request
 import okhttp3.Response
 import okhttp3.WebSocket
 import okhttp3.WebSocketListener
+import kotlin.time.Duration.Companion.milliseconds
 
 private const val TAG = "WalletNotifService"
 
@@ -271,7 +272,7 @@ class WalletNotificationService : Service() {
 
         reconnectJob?.cancel()
         reconnectJob = serviceScope.launch {
-            delay(backoff)
+            delay(backoff.milliseconds)
             openWebSocket()
         }
     }