Change upstream location of testdata to UHH Gitlab

[olemke]

If a download fails, output the actual RequestException error message.
Reduce outer retry attempts from 30 to 2 (each of those already retries up to 5 times inside the download_file function). Past experience has shown if the download fails once, it'll keep failing no matter how many retries are done.

[olemke]

@riclarsson: I decided to not move the download mechanism into cmake. Reason being that the cmake file macro will be executed at configuration time instead of build time, which is not what we want. To do the download at build time, it would need to be implemented inside a cmake script that is executed at build time. Basically doing the same as our python script is doing now. And I'd prefer to maintain the Python script instead of a cmake script. :-)

[riclarsson]

Ok. But if it's done at configuration, then the build fails after 1 minute instead of 40. I hope the new error output will solve the true issue

[olemke]

We'll see how it goes now and what the actual error is if it happens again. If necessary, we can always change it later. Did it happen to you again? I couldn't reproduce the download failure a single time while working on my branch. :-(

[riclarsson]

Yeah, happened earlier this week. Or today? The random branch merge failed so I reran it.

[riclarsson]

Hehe, I just saw the ❌

[olemke]

Guess I managed to reproduce it now. Windows build failed. And the error is a connection timeout. Unfortunately not clear if the outgoing connection from Github is causing it or the server on the UHH side is temporarily blocking.

[olemke]

Superseded by #1100