Update Rust crate curve25519-dalek to v4.1.3

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
curve25519-dalek (source)	dev-dependencies	patch	4.1.2 -> 4.1.3

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Release Notes

dalek-cryptography/curve25519-dalek (curve25519-dalek)

### [`v4.1.3`](https://togithub.com/dalek-cryptography/curve25519-dalek/blob/HEAD/curve25519-dalek/CHANGELOG.md#413) - Security: Fix timing leak in Scalar subtraction on u32, u64, fiat_u32, and fiat_u64 backends - Fix assorted new warnings and lints from rustc and clippy

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