Update Rust crate allocator-api2 to 0.4.0

[oxide-renovate]

This PR contains the following updates:

Package	Type	Update	Change
allocator-api2	workspace.dependencies	minor	0.2.21 -> 0.4.0

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Release Notes

zakarumych/allocator-api2 (allocator-api2)

v0.4.0

Added

• Implementation of Allocator for &mut A as it was added to core
• Implementation Default for vec::IntoIter
• Suffixed methods to SliceExt

Changed

• Use core::error::Error under "fresh-rust" feature even without "std" feature.
• Serialize for Box<T, A> is relaxed to accept T: ?Sized
• serde_core crate is used instead of serde to remove dependency on serde_derive when some other crate enables "derive" feture in serde

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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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• If you want to rebase/retry this PR, check this box

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This PR has been generated by Renovate Bot.

[oxide-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 allocator-api2@0.2.21 --precise 0.4.0
    Updating crates.io index
error: failed to select a version for the requirement `allocator-api2 = "^0.2.8"`
candidate versions found which didn't match: 0.4.0
location searched: crates.io index
required by package `bumpalo v3.19.0`
    ... which satisfies dependency `bumpalo = "^3.19.0"` of package `iddqd-test-utils v0.1.0 (/tmp/renovate/repos/github/oxidecomputer/iddqd/crates/iddqd-test-utils)`
    ... which satisfies path dependency `iddqd-test-utils` (locked to 0.1.0) of package `iddqd v0.3.17 (/tmp/renovate/repos/github/oxidecomputer/iddqd/crates/iddqd)`