Make span flags accessible in pdata Span

[srikanthccv]

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

👋

I am interested in using the span flags available in the protocol https://github.com/open-telemetry/opentelemetry-proto/blob/9d139c87b52669a3e2825b835dd828b57a455a55/opentelemetry/proto/trace/v1/trace.proto#L112-L133. I don't see a way to achieve it in the latest pdata https://pkg.go.dev/go.opentelemetry.io/collector/pdata/ptrace#Span.

Describe the solution you'd like

Make span (and link) flags available in pdata

Describe alternatives you've considered

Have no alternative solution.