fix: improve lock handling in user session interactions (#36)

Reviewed-on: #36
Reviewed-by: lq64 <lq@blackhole.local>
Co-authored-by: Janis <janis.e.20@gmx.de>
Co-committed-by: Janis <janis.e.20@gmx.de>

knockoutwhistweb/app/logic/game/GameLobby.scala

@@ -185,7 +185,7 @@ class GameLobby private(
   }
   
   private def getPlayerInteractable(userSession: UserSession, iType: InteractionType): AbstractPlayer = {
-    if (!Thread.holdsLock(userSession.lock)) {
+    if (!userSession.lock.isHeldByCurrentThread) {
       throw new IllegalStateException("The user session is not locked!")
     }
     if (userSession.canInteract.isEmpty || userSession.canInteract.get != iType) {

knockoutwhistweb/app/model/sessions/UserSession.scala

@@ -9,7 +9,7 @@ import java.util.concurrent.locks.{Lock, ReentrantLock}
 
 class UserSession(user: User, val host: Boolean) extends PlayerSession {
   var canInteract: Option[InteractionType] = None
-  val lock: Lock = ReentrantLock()
+  val lock: ReentrantLock = ReentrantLock()
 
   override def updatePlayer(event: SimpleEvent): Unit = {
     event match {