Log span name when logging received spans in distributors

[suraciii]

Is your feature request related to a problem? Please describe.

Currently distributor does not write span names into logs when logging spans by enabling log_received_spans, even with include_all_attributes on.

Describe the solution you'd like

Add span name into log context when logging span with all attributes.

For example:

// modules/distributor/distributor.go:581
func logSpanWithAllAttributes(s *v1.Span, logger log.Logger) {
	for _, a := range s.GetAttributes() {
		logger = log.With(
			logger,
			"span_"+strutil.SanitizeLabelName(a.GetKey()),
			tempo_util.StringifyAnyValue(a.GetValue()))
	}

	latencySeconds := float64(s.GetEndTimeUnixNano()-s.GetStartTimeUnixNano()) / float64(time.Second.Nanoseconds())
	logger = log.With(
		logger,
+        	"span_name", s.Name,
		"span_duration_seconds", latencySeconds,
		"span_kind", s.GetKind().String(),
		"span_status", s.GetStatus().GetCode().String())

	level.Info(logger).Log("msg", "received", "spanid", hex.EncodeToString(s.SpanId), "traceid", hex.EncodeToString(s.TraceId))
}

Additional context
We're using span logs with Loki as a workaround for search traces, so span names in logs could improve the search efficiency.

[joe-elliott]

+1 to this addition. please submit a PR if you can.

if you are unable to i can do it.

[suraciii]

@joe-elliott PR opened :)