[IvanBM18]

Bug: b/572846941

This is a pretty small PR focused on adding some tags to the swarming requests so we can generate dashboards using swarming's monarch data.

Changes

• When creating a new swarming task request we now tag them so that monarch dashboards & internal alerts can read this data and react accordingly:

clusterfuzz.{job.platform.lower()}:{command}
# E.g: clusterfuzz.android_emulator.fuzz

• Updated existing UT to verify the existence of this tag at the swarming req