Upgrade generated code to Thrift 0.13.0

It appears that even though we had the CQ to Thrift 0.13.0 updated, we did not update the generated Thrift stubs or our internal dependencies to 0.13.0.

Thrift may have some breaking changes from 0.9.3 to 0.13.0, so it's better if we postpone it to Hawk 2.2.0 if we haven't done it in 2.1.0 after all.