chore: update rust crate axum-extra to v0.9.4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
axum-extra	workspace.dependencies	patch	0.9.3 -> 0.9.4

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Release Notes

tokio-rs/axum (axum-extra)

### [`v0.9.4`](https://redirect.github.com/tokio-rs/axum/releases/tag/axum-extra-v0.9.4): axum-extra - v0.9.4 [Compare Source](https://redirect.github.com/tokio-rs/axum/compare/axum-extra-v0.9.3...axum-extra-v0.9.4) - **added:** The `response::Attachment` type ([#​2789]) [#​2789]: https://redirect.github.com/tokio-rs/axum/pull/2789

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Configuration

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♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

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[kodiakhq[bot]]

This PR currently has a merge conflict. Please resolve this and then re-add the automerge label.