fix variable name

Author: xGinko

shared/src/main/java/me/xginko/aef/utils/permissions/BukkitPermissionHandler.java

@@ -75,11 +75,11 @@ private void onPlayerKick(PlayerKickEvent event) {
         flushCache(event.getPlayer());
     }
 
-    private void flushCache(Permissible commandSender) {
-        if (permissionCacheMap.containsKey(commandSender)) {
-            permissionCacheMap.get(commandSender).invalidateAll();
-            permissionCacheMap.get(commandSender).cleanUp();
-            permissionCacheMap.remove(commandSender);
+    private void flushCache(Permissible permissible) {
+        if (permissionCacheMap.containsKey(permissible)) {
+            permissionCacheMap.get(permissible).invalidateAll();
+            permissionCacheMap.get(permissible).cleanUp();
+            permissionCacheMap.remove(permissible);
         }
     }
 }