doc: add github permissions groupsCacheTTL guidance (!24344) · Merge requests · Warren Gifford / sourcegraph · GitLab

Warren Gifford requested to merge docs/groups-cache-ttl-guidance into main Aug 26, 2021

Created by: bobheadxi

groupsCacheTTL guidance
improved spacing in permissions page

follow-up https://github.com/sourcegraph/sourcegraph/pull/23978