chore(deps): update rust crate axum to v0.8.4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
axum	workspace.dependencies	patch	0.8.3 -> 0.8.4

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Release Notes

tokio-rs/axum (axum)

v0.8.4: axum v0.8.4

Compare Source

• added: Router::reset_fallback (#​3320)
• added: WebSocketUpgrade::selected_protocol (#​3248)
• fixed: Panic location for overlapping method routes (#​3319)
• fixed: Don't leak a tokio task when using serve without graceful shutdown (#​3129)

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Configuration

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[renovate]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
• you rename this PR's title to start with "rebase!" to trigger it manually

The artifact failure details are included below:

File name: Cargo.lock

Command failed: cargo update --config net.git-fetch-with-cli=true --manifest-path Cargo.toml --package [email protected] --precise 0.8.3
    Updating crates.io index
error: failed to select a version for the requirement `axum = "^0.7"`
candidate versions found which didn't match: 0.8.3
location searched: crates.io index
required by package `tonic v0.12.3`
    ... which satisfies dependency `tonic = "^0.12.3"` (locked to 0.12.3) of package `indexer-dips v0.1.0 (/tmp/renovate/repos/github/graphprotocol/indexer-rs/crates/dips)`