Include the history tag string in checkin file verbatim

This is done when the history tag pool overflows - otherwise
the tag wouldn't be included in the output at all.

Bug: 274242119
Bug: 300513898
Test: PowerStatsTests:BatteryStatsHistoryTest
Change-Id: I68cf65dd5285864bbf38115321da944d95c7438d
Merged-In: I68cf65dd5285864bbf38115321da944d95c7438d
(cherry picked from commit 49fa85a1)