Related ticket SERVER-59512 recently introduced a new API to DBClientBase for performing find operations. This API accepts a FindCommandRequest, in contrast to the legacy DBClientBase::query() overloads. The legacy DBClientBase::query() API requires the caller to specify the find operation as though it were an OP_QUERY find. This is undesirable because the system no longer supports OP_QUERY find. Therefore, the internal client code is required to upconvert the OP_QUERY find description into an OP_MSG find command before actually sending it over the wire.

The goal of this ticket is to move callers of the legacy DBClientBase::query() API onto the new DBClientBase::find() API. Once this migration is complete, the code which implements DBClientBase::query(), including the special upconversion logic mentioned above, should be deleted. This may need to be done in multiple steps, depending on the complexity and the scope of the code changes.