graphql: get rid of unused variables in graphql/validate.lua

Author: olegrok

cartridge/graphql/validate.lua

@@ -1,8 +1,6 @@
 local path = (...):gsub('%.[^%.]+$', '')
 local rules = require(path .. '.rules')
-local util = require(path .. '.util')
 local introspection = require(path .. '.introspection')
-local schema = require(path .. '.schema')
 
 local function getParentField(context, name, count)
   if introspection.fieldMap[name] then return introspection.fieldMap[name] end