Fix incomplete read

[wasjabloch]

What does this PR do?

Handle IncompleteRead exception by giving the user a hint on how to circumvent it.

Why was it initiated? Any relevant Issues?

fixes #3028

PR Checklist

• Correct base branch selected? master for new features, maintenance_... for bug fixes
• This PR is not directly related to an existing issue (which has no PR yet).
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[wasjabloch]

Sorry, this should be merged into maintenance_1.3.x, which changed during refresh.

[wasjabloch]

IncompleteRead does not have a message attribute, which is why we are raising HTTPException instead. The IncompleteRead will still show up in the traceback.

[megies]

Looks good to me. 👍
I'll retrigger CI so we get FDSN tests run..

[megies]

You could add a changelog one-liner, but it's a small change so I'm also OK with not having one.

[megies]

Thanks!

[megies]

Added you to the devs team too, so you can push branches to main repo next time if you prefer that.