Summary:
DBGet p95 and p99 have high variation, remove them for now.
Also increase the iteration to 3 to avoid false positive.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/9742
Test Plan: Internal CI
Reviewed By: ajkr
Differential Revision: D35082820
Pulled By: jay-zhuang
fbshipit-source-id: facc1d56b94e54aa8c8852c207aae2ae4e4924b0