Renaming isCredentialSharedWithParent to isCredentialSharableWithParent

Renaming isCredentialSharedWithParent to isCredentialSharableWithParent,
as for work profile there is possibility to enroll its own credential.

Bug: 222108271
Test: atest android.multiuser.cts.UserManagerTest
atest LockSettingsServiceTests

Change-Id: If343342d0a5e996cbd430a4063b25fbc4874c5c0
Merged-In: If343342d0a5e996cbd430a4063b25fbc4874c5c0
(cherry picked from commit ece66c41)