Changed error handling for non-GraphQL errors

[sameer-coder]

Closes #543

cc: @simoneb

[sameer-coder]

Added a new test case and updated some existing ones. Please review

[simoneb]

I don't think this is doing what we want to do. Don't we want to keep returning an array of errors but simply provide a more informative error about the inner error?

[sameer-coder]

The inner error message is already being set as the message property on the error in the existing implementation. I am not sure if we have any more information about the error other than the error message.

[mcollina]

@jonnydgreen could you take a look?

[sameer-coder]

@jonnydgreen I have updated the docs. Can you please take a look? Thanks

[mcollina]

@jonnydgreen this seems a semver-major change. wdyt?

[jonnydgreen]

@jonnydgreen this seems a semver-major change. wdyt?

Yeah definitely - especially as we will now be returning a different error responses in certain situations

[mcollina]

right! sounds like a plan!

[mcollina]

I had to revert this change because of #860, we must use 200 everywhere.

[simoneb]

Amazing memory @mcollina !