Search UI - Implement Issue scope results filter by confidentiality

Allow users to filter Search Issues tab results by the confidentiality field (All, Confidential, or Not Confidential)via a drop down. The drop down should default to Any Status.

UI designs are in the related issue (soon to be promoted to an epic)

Documentation updates should be included if appropriate

Design proposal

• #238314[_238314-status-filtering-opened-MVC.png]

Prototype

• Design spec

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