[AAPM] Update ActionDisabledByAdminDialog and ExternalSourcesDetails strings

The new advanced protection support intent will be launched by the
existing ActionDisabledByAdminDialog if the enforcing admin of a certain
restriction is advanced protection. To determine that, Change-Id
If931dcddad508f88aac1280b587da4767b937875 introduces an API to query the
enforcing admin.

In addition, this change updates ExternalSourcesDetails to display
a disabled by advanced protection string in the preference summary.

Tests will be written in a follow up change.

Bug: 358229113
Bug: 369361373
Test: manual
Test: atest ActionDisabledByAdminDialogTest
Test: atest ExternalSourcesDetailsTest
Test: atest LocationInjectedServicesPreferenceControllerTest
Flag: android.security.aapm_api
Flag: android.security.aapm_feature_disable_install_unknown_sources
Change-Id: Icedef421d65f7ccde6562734e39a87d4458567ff