Refactor custom 'display()' functions to use the 'Display' trait

[chshersh]

See the discussion in #83

The idea is to implement the std::fmt::Display trait for data types where we already use a custom display() function. Specifically:

• [ ] TomlError::display
  • https://github.com/chshersh/tool-sync/blob/b79eeb91cfdc3a122e6693d503117f68ff1fb44e/src/config/toml.rs#L16-L24
• [ ] ToolError::display
  • https://github.com/chshersh/tool-sync/blob/b79eeb91cfdc3a122e6693d503117f68ff1fb44e/src/model/tool.rs#L20-L29
• [ ] UnpackError::display
  • https://github.com/chshersh/tool-sync/blob/b79eeb91cfdc3a122e6693d503117f68ff1fb44e/src/sync/archive.rs#L27-L37

Implementation example:

enum TestEnum {
    Var1(String),
    Var2(String),
}

impl fmt::Display for TestEnum {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            TestEnum::Var1(s) => write!(f, "[VAR1]: {}", s),
            TestEnum::Var2(s) => write!(f, "[VAR2]: {}", s),
        }
    }
}

[zixuan-x]

Sicne I just worked with implementing Display trait, this issue is probably a good one for me to get more familiar with the code base. If it's not taken then I'll start working on it?

[chshersh]

@zixuanzhang-x Sounds like an excellent next issue 🥇

It's not taken. And I think @MitchellBerend will be really pleased when this one is done so we can unlock:

• 98