tarantoolctl: disable user-mode for root

tarantoolctl must not search for configuration in
PWD if started by root

extra/dist/tarantoolctl.in

@@ -197,6 +197,10 @@ local function check_cmd(cmd)
 end
 
 local function check_user_level()
+    local uid = os.getenv('UID')
+    if uid == 0 then
+        return nil
+    end
     -- local dir configuration
     local pwd = os.getenv('PWD')
     if pwd ~= nil then