Fix wrong variable being checked. Fixes #233

Spigot-Server-Patches/Only-refresh-abilities-if-needed.patch

@@ -12,7 +12,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
  
      @Override
      public void setFlying(boolean value) {
-+        boolean needsUpdate = getHandle().abilities.canFly != value; // Paper - Only refresh abilities if needed
++        boolean needsUpdate = getHandle().abilities.isFlying != value; // Paper - Only refresh abilities if needed
          if (!getAllowFlight() && value) {
              throw new IllegalArgumentException("Cannot make player fly if getAllowFlight() is false");
          }