Looks like [Jaeger Exporter](https://github.com/open-telemetry/opentelemetry-python/blob/master/ext/opentelemetry-ext-jaeger/src/opentelemetry/ext/jaeger/__init__.py#L131) does not handle SpanKind field of spans during translation from OpenTelemetry's Span to Jaeger's Span. In my opinion, we should just add `'span.kind'` to attributes of Jaeger's Span.
Looks like Jaeger Exporter does not handle SpanKind field of spans during translation from OpenTelemetry's Span to Jaeger's Span.
In my opinion, we should just add
'span.kind'to attributes of Jaeger's Span.