There's a merged pull request on the void-packages repository

Rust 1.70
https://github.com/void-linux/void-packages/pull/44220

Description:
- rust-bootstrap: update to 1.70.0
- cargo-bootstrap: update to 1.70.0
- rust: update to 1.70.0
- cargo: update to 1.70.0
- common/environment/build-style/cargo.sh: remove obsolete sparse crates.io config

Cargo tag missing: https://github.com/rust-lang/cargo/issues/12216

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#### Testing the changes
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