Wrap System.stacktrace() in try/catch block in Transaction tests (#467)
Wrap System.stacktrace() in try/catch block in Transaction tests (#467)

* Wrap System.stacktrace() in try/catch block in Transaction tests

Closes #460

* fixup! Wrap System.stacktrace() in try/catch block in Transaction tests

appsignal/appsignal-elixir,appsignal/appsignal-elixir,appsignal/appsignal-elixir,appsignal/appsignal-elixir