Improve cross-world teleportation handling

By: md_5 <git@md-5.net>

paper-server/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java

@@ -1075,6 +1075,7 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         if (fromWorld == toWorld) {
             entity.connection.teleport(to);
         } else {
+            entity.portalProcess = null; // SPIGOT-7785: there is no need to carry this over as it contains the old world/location and we might run into trouble if there is a portal in the same spot in both worlds
             // The respawn reason should never be used if the passed location is non null.
             server.getHandle().respawn(entity, true, Entity.RemovalReason.CHANGED_DIMENSION, null, to);
         }