Fix wood farmers becoming stuck in trees

kai/woodfarm.lua

@@ -169,7 +169,10 @@ local state_machine = {
     ["FINALIZE_TREE"] = function()
         -- make sure we are directly above the sapling target
         while T.state.y > 0 do
-            T.down()
+            while not T.down() do
+                -- another tree might have spawned leaves below us
+                turtle.digDown()
+            end
         end
 
         turtle.select(SAP_SLOT)