Update main.rb

[hawjefferson]

Change host URL based on the mparticle hosting instance. The free trial is running on us2 pod hence the host needs to be changed.

Summary

• {provide a thorough description of the changes}

Testing Plan

• {explain how this has been tested, and what additional testing should be done}

Master Issue

• Closes https://go.mparticle.com/work/REPLACEME