Tweak status display logic and tests

The existing logic and tests looks incorrect. Tests have been tidied up
to reflect real cases. For example, it's not really possible for the
provider to report being "blocked", but for it to report it is "certain"
at the same time.

Bug: 266921482
Test: atest tests/robotests/src/com/android/settings/datetime/LocationProviderStatusPreferenceControllerTest.java
Change-Id: I1a0faa44ed7dd09828ff758db9e40f5d5e010ab0