Change alerting channels for DX tooling
Description
Things to consider:
determine who should receive what alerts (test failures, job failures in general, AWS alerts, New Relic alerts, Github)
determine what to do with the testeng gmail group -> should devops join this? should other people join this? should we use a different group
determine which slack channels should be used for alerting. Currently, jenkins job statuses are sent to `new-jenkins-chatter` but perhaps this isn't optimal post-transition.
Once these decisions have been made:
change account level alerting (i.e. the email address to receive alerts in GH, new relic)
change any jenkins jobs to alert the appropriate teams
make any necessary changes to the jenkins global config with regards to alerting
change any automation that alerts an individual DX team member