Add updateMccMncConfiguration as @TestApi for CTS

Test: cts; https://paste.googleplex.com/5930499648258048
Bug: 147897445
Change-Id: I63288be1acd9e898548ced345799ac1ae69ce427
Merged-In: I63288be1acd9e898548ced345799ac1ae69ce427
(cherry picked from commit 3d873cf7d0dafde39793313b0b532a0bd163705f)
2 files changed