fix(lua): luap injection (#5275)

* fix(lua): luap injection

* test(lua): check for incorrect hlgroup of injected luap

* chore(lua): injections styling

* chore(lua): ignore luacheck for test.lua

tests/query/highlights/lua/test.lua

@@ -1,3 +1,4 @@
+-- luacheck: ignore
 local a = { 1, 2, 3, 4, 5 }
 --          ^ number      ^ punctuation.bracket
 --    ^ variable
@@ -11,3 +12,7 @@ _ = next(a)
 
 next(a)
 -- ^ function.builtin
+
+-- Checking for incorrect hlgroup of injected luap
+string.match(s, "\0%d[^\n]+")
+--                       ^ !constant