4.6x30mm Ammunition Boxes Are No Longer Invisible (shiptest-ss13#2859)

<!-- Write **BELOW** The Headers and **ABOVE** The comments else it may
not be viewable. -->
<!-- You can view Contributing.MD for a detailed description of the pull
request process. -->

## About The Pull Request
Turns out adding a . in a dmi frame broke it. Who woulda thunk it.
<!-- Describe The Pull Request. Please be sure every change is
documented or this can delay review and even discourage maintainers from
merging your PR! -->

## Why It's Good For The Game
No more broken sprite.
<!-- Please add a short description of why you think these changes would
benefit the game. If you can't justify it in words, it might not be
worth adding. -->

## Changelog

:cl: PositiveEntropy
fix: The 4.6x30mm ammunition box is no longer invisible.
/:cl:

<!-- Both :cl:'s are required for the changelog to work! You can put
your name to the right of the first :cl: if you want to overwrite your
GitHub username as author ingame. -->
<!-- You can use multiple of the same prefix (they're only used for the
icon ingame) and delete the unneeded ones. Despite some of the tags,
changelogs should generally represent how a player might be affected by
the changes rather than a summary of the PR's contents. -->

code/modules/projectiles/boxes_magazines/ammo_boxes.dm

@@ -400,7 +400,7 @@
 /obj/item/ammo_box/c46x30mm_box
 	name = "ammo box (4.6x30mm)"
 	desc = "A box of standard 4.6x30mm ammo."
-	icon_state = "4.6x30mmbox"
+	icon_state = "46x30mmbox"
 	ammo_type = /obj/item/ammo_casing/c46x30mm
 	max_ammo = 50