[devtools] drop unused `reset_schema` and `reset_vreg` class attribute
They have no effect and no user...
Related to #2944813
/*
* cubicweb js mock for unit tests
* This module defines variables and functions used in quite a few places
* in cw js framework that can't be used or guessed without a real CW server
*/
var pageid = 'my-page-id';
function _(message) {
return message;
}