DO Disclosures: Combine personal and work CA cert

It was decided that rather than having two separate items for CA certs
in the personal and work spaces, we should have just one item that
lists the sum of installed certs.

Bug: 32692748
Test: m RunSettingsRoboTests

Change-Id: Ic8a3db214a07992e3970262c2ce91f3df8a87773