If using a different prometheus Registry than the default the inprogress Gauge is wrongly defined

[sanderegg]

in instrumentation.py, it is missing the argument to pass the registry to the created Gauge.

# instrumentation.py
  self.inprogress: Optional[Gauge] = None
        if self.should_instrument_requests_inprogress:
            labels = (
                (
                    "method",
                    "handler",
                )
                if self.inprogress_labels
                else ()
            )
            self.inprogress = Gauge(
                name=self.inprogress_name,
                documentation="Number of HTTP requests in progress.",
                labelnames=labels,
                multiprocess_mode="livesum", # the registry is not passed here.
            )