Icon smoothing for asteroid rocks (#8058)

Co-authored-by: Tomeno <tomeno@lulzsec.co.uk>

Resources/Textures/Structures/Walls/asteroid_rock.rsi/meta.json

@@ -1 +1 @@
-{"version": 1, "size": {"x": 32, "y": 32}, "states": [{"name": "0", "delays": [[1.0]]}, {"name": "1", "delays": [[1.0]]}, {"name": "2", "delays": [[1.0]]}, {"name": "3", "delays": [[1.0]]}, {"name": "4", "delays": [[1.0]]}]}
+{"version": 1, "license": "CC-BY-SA-3.0", "copyright": "https://github.com/discordia-space/CEV-Eris/commit/a0c067f688288aeb167157203e2170b14cfa9d7f", "size": {"x": 32, "y": 32}, "states": [{"name": "rock_0", "directions": 4}, {"name": "rock_1", "directions": 4}, {"name": "rock_2", "directions": 4}, {"name": "rock_3", "directions": 4}, {"name": "rock_4", "directions": 4}, {"name": "rock_5", "directions": 4}, {"name": "rock_6", "directions": 4}, {"name": "rock_7", "directions": 4}, {"name": "full"}]}