Default to a shallow checkout of the libtcod submodule.

HexDecimal · HexDecimal · commit af0806d86b9d · 2021-06-03T10:42:11.000-07:00
diff --git a/.gitmodules b/.gitmodules
@@ -1,3 +1,4 @@
 [submodule "libtcod"]
 	path = libtcod
 	url = https://github.com/libtcod/libtcod
+	shallow = true
