style(tools/module): improve code style for readability (#12798)

kong/tools/module.lua

@@ -15,17 +15,18 @@ local _M = {}
 -- @return success A boolean indicating whether the module was found.
 -- @return module The retrieved module, or the error in case of a failure
 function _M.load_module_if_exists(module_name)
-  local status, res = xpcall(function()
-    return require(module_name)
-  end, debug.traceback)
+  local status, res = xpcall(require, debug.traceback, module_name)
+
   if status then
     return true, res
+  end
+
   -- Here we match any character because if a module has a dash '-' in its name, we would need to escape it.
-  elseif type(res) == "string" and find(res, "module '" .. module_name .. "' not found", nil, true) then
+  if type(res) == "string" and find(res, "module '" .. module_name .. "' not found", nil, true) then
     return false, res
-  else
-    error("error loading module '" .. module_name .. "':\n" .. res)
   end
+
+  error("error loading module '" .. module_name .. "':\n" .. res)
 end