Improve Oban error reporting

[whatyouhide]

• We don't report {:discard or {:cancel return values
• We unwrap Oban.PerformErrors if the return value is an exception
• Moar tests

[mbaleczny]

Hi @whatyouhide 👋 FYI It looks like this PR changes makes this part of the documentation invalid. Is there any other easy way to avoid reporting handled errors {:error, reason}, {:cancel, reason}, {:discard, reason}?

[whatyouhide]

@mbaleczny wait, I am not sure what it is you want to do. Start reporting those again, or stop reporting them?

[mbaleczny]

@whatyouhide I want to stop reporting them. But I want the crashed and timed out oban jobs being reported. That used to work when errors were wrapped with Oban.PerformError.

[whatyouhide]

That's how things should be working now: Only reports crashes, but not :cancels and :discards. I'll need a bit more info about this as this is the first report of this not working as expected. Could you please open up an issue?