upgrade cargo, cargo-platform dependencies to support the 2024 edition.

[eric-seppanen]

Without this change, cargo crev verify always prints:

failed to load manifest for workspace member `.../crates/some_crate`
referenced by workspace at `.../my_workspace/Cargo.toml`

Caused by:
    0: failed to parse manifest at `.../crates/Cargo.toml`
    1: feature `edition2024` is required
       
       The package requires the Cargo feature called `edition2024`, but that feature is not stabilized in this version of Cargo (1.84.0).
       Consider adding `cargo-features = ["edition2024"]` to the top of Cargo.toml (above the [package] table) to tell Cargo you are opting in to use this unstable feature.
       See https://doc.rust-lang.org/nightly/cargo/reference/unstable.html#edition-2024 for more information about the status of this feature.

Checklist:

• cargo +nightly fmt --all

I did not do this as it changes the formatting of existing code, unrelated to this PR which does not change any .rs files. Maybe formatting should be checked in CI instead?

• Modify CHANGELOG.md if applicable