[mainline] getTetherApnRequired API rename to isTetherApnRequired

Bug: 142365448
Test: Build pass.
      atest TetheringConfigurationTest (PASS)

Change-Id: I80f2dc99f14057c98a9855de9987c4d8b34dffa3
Merged-In: I80f2dc99f14057c98a9855de9987c4d8b34dffa3
1 file changed