luacheck: fix warnings in test/box

Follows up #5455

test/box/gh-5304-insert_during_recovery.lua

 #!/usr/bin/env tarantool
 
-function none(old_space, new_space)
+local function none(old_space, new_space) -- luacheck: ignore
 end
 
-function trigger_replace(old_space, new_space)
+local function trigger_replace(old_space, new_space) -- luacheck: ignore
     box.space.temp:replace({1})
     box.space.loc:replace({1})
 end
 
-function trigger_insert(old_space, new_space)
+local function trigger_insert(old_space, new_space) -- luacheck: ignore
     box.space.temp:insert({1})
     box.space.loc:insert({1})
 end
 
-function trigger_upsert(old_space, new_space)
+local function trigger_upsert(old_space, new_space) -- luacheck: ignore
     box.space.temp:upsert({1}, {{'=', 1, 4}})
     box.space.loc:upsert({1}, {{'=', 1, 4}})
 end
 
-trigger = nil
+local trigger = nil
 
 if arg[1] == 'none' then
     trigger = none

test/box/gh-5304-replace_during_recovery.lua

@@ -2,6 +2,7 @@
 
 if arg[1] == 'replace' then
     box.ctl.on_schema_init(function()
+        -- luacheck: ignore
         box.space._index:on_replace(function(old_space, new_space)
             if new_space[1] == 512 then
                 box.space.test:on_replace(function(old_tup, new_tup)