Erroneous Jobs send a message and report "returncode: 0"

Even if a TOS Job exits with a non-zero exit code (e.g. using tDie), a message is created and returncode 0 is reported to AW. This misbehavior happens due to a bug in uvicorn:

https://github.com/encode/uvicorn/issues/894

I am monitoring this issue and will update this dependency asap when a fix is provided.