SettingsUnitTests: migrate to @SystemApi Builders for WifiInfo & NetworkSelectionStatus

Use the newly created Builder classes to construct
WifiInfo & NetworkSelectionStatus with the
appropriate fields set, so that they can be
parceled/unparceled.

Bug: 138801922
Test: atest SettingsUnitTests
Change-Id: I8dd6bc5d51d1a41ff4b8b2760faaa00b633fc2f7