Updating intent to use system services only.

ExplicitHealthCheckController is filtering the system services libraries by setting the package name.
We could simply pass the MATCH_SYSTEM_ONLY flag instead.
This way we could stop depending on
`getServicesSystemSharedLibraryPackageName` hidden API.

Bug: 338468233
Test: verified that ExplicitHealthCheckServiceImpl is connected
Flag: android.crashrecovery.flags.refactor_crashrecovery
Change-Id: Ie602aefd1280022fc6965ad31e4d872c33904dd9