Arrow slot icon fails to load due to extra semicolon in api.lua

[Former user]

Line 2216 of api.lua has:

'image[0,0.5;1,1;x_bows_arrow_slot.png;]',

Need to remove that final ;

[Juraj Vajda]

Thank you for pointing it out! Fixed here https://bitbucket.org/minetest_gamers/x_bows/pull-requests/15