chore: update toolchain to 1.84.1. apply clippy fixes & rustfmt

[dsully]

What does this PR do

Updates rust-toolchain.toml to "stable" (currently 1.84.1) and runs clippy --fix + rustfmt

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[SteveLauC]

Updates rust-toolchain.toml to "stable"

I pinned it to the MSRV purposely to make packaging easier.

Is there any reason why you want to change it to the latest stable toolchain?

runs clippy --fix + rustfmt

Thanks for fixing the Clippy issue

[dsully]

Hi @SteveLauC - I have another PR that I've not put up yet that removes lazy_static and once_cell in favor of std::sync::LazyLock, which is why I wanted to bump the MSRV / toolchain version.

[SteveLauC]

That sounds reasonable! 😄 Please pin the toolchain to the MSRV rather than "stable"

[SteveLauC]

Looks good, thanks!