ECDSA signature generation does not follow RFC-6979

[pmerkleplant]

The ECDSA signatures generated by the vm.sign() cheatcode do not strictly follow RFC-6979. For more info regarding the details, see this analysis.

Note that the underlying ECDSA functionality is provided via RustCrypto which fixed the issue in a recent prerelease, see RustCrypto/elliptic-curves#1100.

Creating this as tracking issue, can be closed once foundry updates to the new RustCrypto version.

[zerosnacks]

For future reference: Foundry is using this through the k256 crate and we are waiting for the 0.14 release to land: https://crates.io/crates/k256/versions

alloy-core also re-exports k256, added a tracking ticket for that here: alloy-rs/core#837