Allow services enabled after force close

When an A11y service is enabled, it would be added into the list
of the crashed services after doing force close. Then users can't
enable this service until users disable this service again based
on our crashed mechanism now.

The A11y service would be removed from the list of enabled
services after doing force close. We need to remove this service
from the list of the crashed service at the same time to make sure
users can enable this service next time immediately.

Bug: 174616279
Test: a11y CTS & unit tests
Test: manual testing by the steps in the bug
Change-Id: Ie09a11dd2eb2ed7237b580e69c46751ef404b96a