fix(deps): Bump luautf8 dependency to restore building against latest LuaJIT

c.f. starwing/luautf8#55

Author: alerque

sile.rockspec.in

@@ -41,7 +41,7 @@ dependencies = {
    "luarepl == 0.10-1",
    "luasec == 1.3.2-1",
    "luasocket == 3.1.0-1",
-   "luautf8 == 0.1.5-2",
+   "luautf8 == 0.1.6-1",
    "penlight == 1.14.0-2",
    "vstruct == 2.1.1-1",
 }