Revamp BinaryTransparencyService.

BinaryTransparencyService:
- change default binary measurement method from SHA256 digest to
  APK content digest. This allows for more performant measurements.

- got rid of in-memory caches of digest results because:
  a) larger scope: more binaries will be covered (in the magnitude
     of hundreds);
  b) the digest length using APK content digest might be longer than
     256 bits: e.g. CHUNKED_SHA512 which is 512 bits;
  c) the computation of these new digests are not as computationally
     intensive that it causes noticible lags even when commands are
     invoked repeatedly in adb shell.

- changed scheduled job to be scheduled periodically (once in a 24
  hour period) instead of a one-off job.

- make use of method calls to BackgroundInstallControlService (BICS)
  to obtain list of newly installed mobile bundled apps (MBAs).

BinaryTransparencyServiceTest:
- modified the return type for `getApexInfo` to receive a List instead
 of Map.

Bug: 245944666

Test: atest BinaryTransparencyServiceTest.
      Also, adb shell cmd jobscheduler run android <job-id>.
      <job-id> can be found in debug printouts with TransparencyService
      tag.
Change-Id: Ie305e71c514f4fb65b9e640301093ec83f01f718