Update App to App Signature generation to use UTC
Standardizing all app to app validation in server and client to use UTC to prevent timezone issues.
https://gitlab.fs.eckler.ca/life-2/gatekeeper-go/blob/master/authenticate.go#L54
Standardizing all app to app validation in server and client to use UTC to prevent timezone issues.
https://gitlab.fs.eckler.ca/life-2/gatekeeper-go/blob/master/authenticate.go#L54