Update Rust crate axum to v0.7.9

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
axum	dependencies	patch	0.7.8 -> 0.7.9

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Release Notes

tokio-rs/axum (axum)

### [`v0.7.9`](https://redirect.github.com/tokio-rs/axum/releases/tag/axum-v0.7.9): axum - v0.7.9 [Compare Source](https://redirect.github.com/tokio-rs/axum/compare/axum-v0.7.8...axum-v0.7.9) - **fixed:** Avoid setting content-length before middleware ([#​3031]) [#​3031]: https://redirect.github.com/tokio-rs/axum/pull/3031

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Configuration

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