There is an um cli option to disable alerting for terminal state of events. The option name is "terminalEventState.alertEnabled". You may set this option to false to disable alerting on event terminal state. The command to disable this option is:
"um option set terminalEventState.alertEnabled=false"
Note: If you are using vApp as UM server, you will have to do this via support.
I agree that we should get an option to turn these emails off. All of our other monitoring tools are set to email on errors, but not to email on resolution. If you insist on keeping the emails please can you at least change obsolete to something meaningful!
Obsolete doesn't to me say that the issue has been fixed.