XDCR - DcpStats command should use filter to lighten work on KV

MB-47198 was the previous work on alleviating load for source KV.
However, more work can be done as XDCR can just request a subset of information from the STAT command.

6/15/2023:
The CBSE that found this issue was on 6.6.1, so it is possible that MB-47198 could have relieved that situation from happening without the need for this.