Remove unused Row index.
Remove unused Row index.

See this comment for a summary of the Row queries:
https://github.com/catapult-project/catapult/issues/4440#issuecomment-394947024
The only query that orders by revision ascending is in
graph_data.GetRowsForTestBeforeAfterRev, and it does not project value, so it
does not use this index.

I'll clean this up tonight and keep an eye on the logs. If NeedIndexErrors or
timeouts show up, then I'll recreate it. It might take a few days to recreate,
but next week should be a light week for most users.

Bug: catapult:#4440
Change-Id: Icc623d6677c92c3d88317c3328ac7a2c4153c7b7
Reviewed-on: https://chromium-review.googlesource.com/1120642
Reviewed-by: Simon Hatch <490a224d89645d3fea983d7189ce51bde0a00c1d@chromium.org>
Commit-Queue: Ben Hayden <d3ffe0e065c2328e497bb32a07f4dcb29138ef5b@chromium.org>

catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult