Update the logic of querying crashed a11y services

Bug: 129689483
Test: a11y CTS & unit tests
Test: manual
      1. Install and enable an intentional crashed a11y service.
      2. After it's crashed and malfunctioning, re-enable it.
      3. Check if it's bound again.

Change-Id: Ifda4fddfbe9b38841f5cc143c32ab1d2f059350c