Support internal and client spans from cosmos db

[lmolkova]

Addressing portal team feedback on new Cosmos instrumentation:

• in Direct (TCP mode), Cosmos will set Client kind on activities. Even though Cosmos uses TCP, some rare HTTP requests will be made under these activities, so there will be a few occasional client->client spans.
• In Gateway (HTTP mode), Cosmos will set Internal kind on activities. Users are expected to get both internal (logical) activities and nested HTTP calls.

[sourabh1007]

looks good!!

[reyang]

LGTM with a changelog entry.

[lmolkova]

LGTM with a changelog entry.

thank you @reyang! I updated the changelog.

[lmolkova]

thank you @TimothyMothra !