Feature Request: ScrollService.Clear() with scrollId param

[david-dietz]

Please use the following questions as a guideline to help me answer your issue/question without further inquiry. Thank you.

Which version of Elastic are you using?

[X] elastic.v7 (for Elasticsearch 7.x) [ ] elastic.v6 (for Elasticsearch 6.x) [ ] elastic.v5 (for Elasticsearch 5.x) [ ] elastic.v3 (for Elasticsearch 2.x) [ ] elastic.v2 (for Elasticsearch 1.x)

Please describe the expected behavior

I want to be able to clear a specific scrollId, not just the current one on the ScrollService. That way after a function is done processing a batch (say batch 123) it can get another batch (456) using the scrollId from batch 123, then after batch 456 is returned it can clear batch 123's scrollId.