Improved Wild Strike (Circle of the Moon Druids Lv.10)
The page for Circle of the Moon Druids states, that you get the Improved Wild Strike at Lv. 10: "You can make 2 additional attacks after making an unarmed strike while in wildshape"
I am not so far in the game to confirm this though... yet!
Warlocks
Warlocks with Pact of the Blade also get Extra Attack at level 5, but I have no idea how to edit the page to reflect this.