Fix the test_move_unit_in_circle test

Just needed to extract the unit earlier, so that it wouldn't be counted as blocking itself

Closes #4635

data/lua/wml/move_unit.lua

@@ -79,6 +79,7 @@ function wesnoth.wml_actions.move_unit(cfg)
 			local pass_check = nil
 			if check_passability then pass_check = current_unit end
 
+			current_unit:extract()
 			local x, y = locs(current_unit)
 			local prevX, prevY = tonumber(current_unit.x), tonumber(current_unit.y)
 			while true do
@@ -98,7 +99,6 @@ function wesnoth.wml_actions.move_unit(cfg)
 			elseif current_unit.x > x then current_unit.facing = "sw"
 			end
 
-			current_unit:extract()
 			local current_unit_cfg = current_unit.__cfg
 			wesnoth.wml_actions.move_unit_fake {
 				type = current_unit_cfg.type,

data/test/scenarios/test_move_unit.cfg

@@ -274,9 +274,7 @@
             [/have_unit]
         )}
 
-        # Move Alice in a circle, ending on the hex that she started on. This will fail if the
-        # implementation chooses a vacant hex based on the starting situation, rather than the
-        # situation before the final nw move.
+        # Move Alice in a circle, ending on the hex that she started on.
         [move_unit]
             id=alice
             dir=sw,s,se,ne,n,nw