I have a Java Spring application that is integrated in datadog APM. I want to reduce the sampling rate for traces to 10%. However, if a trace is from an error, I want it to be included all the time. How can I add this override using the DD_TRACE environment variables?

The environment variables I use to set the current sampling rule for traces is DD_TRACE_SAMPLING_RULES, however as far as I know I can only include a JSNON object with the service name and the sampling rate. There is no option to add a rule to override this sampling rate for errors.