Remove flaky servicelab metrics DBPut P95/P99 (facebook#9844)

Summary:
The P95 and P99 metrics are flaky, similar to DBGet ones which removed
in facebook#9742 .

Pull Request resolved: facebook#9844

Test Plan: `$ ./buckifier/buckify_rocksdb.py`

Reviewed By: ajkr

Differential Revision: D35655531

Pulled By: jay-zhuang

fbshipit-source-id: c1409f0fba4e23d461a65f988c27ac5e2ae85d13