[clang-tools-extra] [Docs][clang-tools-extra] Convert maintainers list to .rst format (PR #165171)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman approved this pull request.

LGTM, feel free to take or leave my suggested changes.

https://github.com/llvm/llvm-project/pull/165171