Retire the Tron metrics reporting for non-A/B update

This is part of the effort to remove libmetricslogger in platform.
Remove the reporting since the status from non-A/B update is less
important to us. Plus the gmscore already has a copy of the logic
to parse the contents from last_install and report non-A/B metrics
to the clearcut log.

bug: 147776349
Test: build
Change-Id: I4fc5d58fb616edb3eb1edadf4614d3eca15c7ce1