Send IncludeEmptyEntriesInMessagePayload capability to host to get empty entries in payload

[kshyju]

For trigger payloads of collection type(ex: event hub trigger payload with batched messages), host will skip empty entries by default. We recently made a host level change so that host will not skip empty entries if worker includes IncludeEmptyEntriesInMessagePayload capability when advertising the capability list to host. The dotnet worker was updated to send this capability if user opts in for that(In the next major version, we will enable it by default). Java worker should consider making similar change.