devel/go-tools: update to 0.30.0

Selected upstream changes:

• cmd: apply modernizers
• tools: fix typos in docs and comments
• godoc,present,refactor: modernize
• x/tools: use types.VarKind consistently
• go.mod: update golang.org/x dependencies

Changelog: https://github.com/golang/tools/compare/v0.29.0...v0.30.0