fix: fix Linux and DragonFlyBSD yes option

[SteveLauC]

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• The PR title is descriptive.
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• The code compiles (cargo build)
• The code passes rustfmt (cargo fmt)
• The code passes clippy (cargo clippy)
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---

What does this PR do

1. Change the yes option from

   .arg(if ctx.config().yes(Step::System) { "-y" } else { "" })

   to

   if ctx.config().yes(Step::System) {
       cmd.arg("-y");
   }

[SteveLauC]

Here is a build for x86_64-unknown-linux-musl, would you like to give it a test? @LordChaos73

Closes #512

[signed-log]

Sorry for introducing that (seems like I didn't test assume_yes=false), I will be able to test on my side too today

[signed-log]

Can repro the original bug, this solves it with assume_yes=false

No regressions on assume_yes=true