ScopeManagerShim.activate(span) throws IllegalArgumentException when null is passed in

[shawnsong]

ScopeManagerShim.activate() throws IllegalArgumentException if a null span is passed in. I'm not sure whether this is a bug or implemented on purpose but it is inconvenient to use as we need to do a null check before calling activate.

Currently, I need to do this to avoid the exception.

try (Scope scope = (span != null ? tracer.scopeManager().activate(span) : null)) {
  ...
}

It would be good if null is returned by the method as try-with-resources doesn't complain a null resource.

What version and what artifacts are you using?
Artifacts: (opentelemetry-opentracing-shim)
Version: (v1,9,1-alpha)

[carlosalberto]

Fixed via #3985

[anpatellll]

@carlosalberto Whats the ETA of this being released?