Improve usefulness of error logging

[dovidgef]

While using this Action many times we received generic errors like:

Error: Action failed with error [object Object]

This PR logs the actual error message from the Error object allowing users to see more helpful error messages.

The error messages now look like:

Error: Action failed with error: The test request will exceed the remaining test balance for the given API key

[dovidgef]

Hi @tkadlec,
I would appreciate it if you could review my PR.

There is one point that I need clarification on, does the property statusText always exist on the Error object?
If not then I can switch back to using JSON.stringify(e) instead.

Thanks

[tkadlec]

This is looking great so far @dovidgef!

There is one point that I need clarification on, does the property statusText always exist on the Error object? If not then I can switch back to using JSON.stringify(e) instead.

In theory, yes. Might be good to add a quick check here, just to be extra resilient.

[dovidgef]

@tkadlec I added a fallback to JSON.stringify() when statusText is undefined.

[dovidgef]

@tkadlec anything else needed to get this merged?

Thanks

[tkadlec]

Appreciate your patience on this @dovidgef! Looks great...merged!