Quarantine mr_widget_options_spec.js

What does this MR do and why?

This spec has failed in this master-broken incident: gitlab-org/quality/engineering-productivity/master-broken-incidents#1472 (closed). I'm going to quarantine this test for now until the flakiness of this spec has been resolved.

Related to #385238 (closed)

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.