Hotfix waiting for world deletion

src/de/steamwar/bungeecore/SubserverSystem.java

@@ -116,8 +116,8 @@ public class SubserverSystem {
         if(eventFightID == -1)
             return new Bauserver(serverName, player1, port, process, () -> {
                 try {
-                    new ProcessBuilder("rm", "-r", ARENA_PATH + finalMapName).start();
-                } catch (IOException e) {
+                    new ProcessBuilder("rm", "-r", ARENA_PATH + finalMapName).start().waitFor();
+                } catch (IOException | InterruptedException e) {
                     throw new SecurityException("Could not clean up folder", e);
                 }
             });
@@ -127,8 +127,8 @@ public class SubserverSystem {
                     return;
 
                 try {
-                    new ProcessBuilder("rm", "-r", ARENA_PATH + finalMapName).start();
-                } catch (IOException e) {
+                    new ProcessBuilder("rm", "-r", ARENA_PATH + finalMapName).start().waitFor();
+                } catch (IOException | InterruptedException e) {
                     throw new SecurityException("Could not clean up folder", e);
                 }
             });