Allow grabbing the tracer log files from parameteric tests

[andrewlock]

I'm trying to debug a parametric test failure, but:

• The tracer logs aren't captured from the container, so there's no way of seeing them
• The containers are always torn down, so there's no way to inspect the logs

[andrewlock]

A hack I used locally was to add

            "dotnet": {"./logs_weblog": "/var/log/datadog"},

to this list of volumes:

https://github.com/DataDog/system-tests/blob/main/utils/_context/_scenarios/parametric.py#L87