fix: softwareupdate under dry run

[schrobingus]

Standards checklist:

• I have read CONTRIBUTING.md
• The PR title is descriptive.
• The code compiles (cargo build)
• The code passes rustfmt (cargo fmt)
• The code passes clippy (cargo clippy)
• The code passes tests (cargo test)
• Optional: I have tested the code myself

This is just a simple fix on the macOS softwareupdate step, as the boolean should_ask wasn't conditional to dry runs prior.

[SteveLauC]

Thanks!