v0.77.3

Dev

• Added manage lint --yaml/--actions and manage prettify --yaml to
  lint and format YAML with yamlfmt, actionlint, and shellcheck;
  wired into CI and tox.

• Reformatted workflow and config YAML with yamlfmt and added a
  riko/cli/.yamlfmt config.

Full Changelog: v0.77.2...v0.77.3