Switch to tombstoned.microdroid

The long term plan is to completely remove tombstoned from microdroid (b/243494912), however it might take time some time to implement it.

In the meantime, we've recently removed cgroups support from the microdroid kernel. This means that starting a tombstoned results in a bunch of non-fatal errors in the logs that are related to the fact that tombstoned service specifies task_profiles.

To get rid of these error messages we temporary add a microdroid variant of the tombstoned (tombstoned.microdroid) that doesn't specify task_profiles.

Bug: 239367015
Test: microdroid presubmit
Change-Id: Ia7d37ede2276790008702e48fdfaf37f4c1fd251