Wandering traders can sell pale oak saplings even when they're disabled

Wandering traders can sell pale oak saplings on worlds without Experimental Features toggled.

How to reproduce:

1. Enter a world that has the Winter Drop experiment disabled.

2. Spawn wandering traders by using spawn eggs or commands until you find one that can sell pale oak saplings.

Expected result:

Wandering traders would not be able to sell pale oak saplings when they're disabled.

Observed result:

Wandering traders can sell pale oak saplings even when they're disabled.