refactor: run pre-sudo before pre-cmds && clear cached credential aft…

[SteveLauC]

Standards checklist:

• The PR title is descriptive.
• I have read CONTRIBUTING.md
• 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

For new steps

• Optional: Topgrade skips this step where needed
• Optional: The --dry-run option works with this step
• Optional: The --yes option works with this step if it is supported by
  the underlying command

If you developed a feature or a bug fix for someone else and you do not have the
means to test it, please tag this person here.

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This PR

1. Move pre-sudo before all the steps
2. Clear cached credential after execution

[SteveLauC]

Here is a build with this patch included: https://github.com/SteveLauC/topgrade/releases/tag/pr565

@agoodshort, would you like to give it a test?

[agoodshort]

Let me find a way to reproduce the issue from #372 and I am happy to test yes!

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May I suggest to update these comments too?

topgrade/src/config.rs

Lines 1427 to 1428 in 3626c9c

	/// If `true`, `sudo` should be called after `pre_commands` in order to elevate at the
	/// start of the session (and not in the middle).

topgrade/config.example.toml

Line 26 in 3626c9c

# Run `sudo -v` to cache credentials at the start of the run

[SteveLauC]

May I suggest to update these comments too?

Sure! Done!

Can I trouble you for a code review on this PR :)

[agoodshort]

Hey @SteveLauC sorry, I am going on holidays tomorrow and didn't have a chance to reproduce the issue. I'm dropping a comment on #372 to see if author would volunteer to test, otherwise I will do it when I'm back. Code looks good, but I don't want to fully review without a proper test.

[SteveLauC]

I am going on holidays tomorrow

Enjoy your holiday! :)

I'm dropping a comment on #372 to see if author would volunteer to test, otherwise I will do it when I'm back. Code looks good, but I don't want to fully review without a proper test.

Sure!

[SteveLauC]

Well, I just realized that pre-sudo should be placed after self_update