Remove DefaultDialerCache spam logging.

The "refresh default dialer for user" log in DefaultDialerCache#refreshCachesForUsersWithPackage was causing logcat spam of 200+ identical logs during one test invocation. This CL reduces the priority of that log to prevent this unneccesary + repetitive logcat spam from occurring.

Bug: 276794351
Test: N/A since this CL just removes logging.
Change-Id: I0f0d1bb1be8f3fcff0bafc957f2e59beca1a0f8c