return 409 on dataset duplicate

[thuibr]

What happened?

Hello,
First of all, thank you for this creating and maintaining this project! We are looking at using it for our development and testing.

I ran into this issue, similar to #66 but with datasets. There is a PR out there, #184, which attempts to resolve the issue, but it seems to have gone stale. I'm filing an issue to raise visibility and to also possibly contribute a fix myself.

What happens is the google bigquery client keeps on trying to create the dataset but getting 500 errors. If its a 4xx error, then I think that the client will quit trying, which is what we want.

What did you expect to happen?

It should produce a 409 error, I believe.

How can we reproduce it (as minimally and precisely as possible)?

Try creating a dataset that already exists in the bigquery emulator as well as the real bigquery.

Anything else we need to know?

No response