Update/prune deps and add outdated recipe (#281)

Deps:
- Update git to 0.20
- Update tempfile to 3.15
- Move pretty assertions and tempfile to dev-deps
- Remove unused strum dep
- Update other deps at the patch version
- Update flake.lock

Justfile:
- Split scan recipe into audit and udeps recipes
- Add outdated recipe

Signed-off-by: Nick Gerace <[email protected]>