chore(deps): update rust crate tokio-tungstenite to 0.21

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
tokio-tungstenite	workspace.dependencies	minor	0.18 -> 0.21

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Release Notes

snapview/tokio-tungstenite (tokio-tungstenite)

v0.21.0

Compare Source

• Update TLS dependencies.
• Update tungstenite to 0.21.0.

v0.20.1

Compare Source

• Fix RUSTSEC-2023-0053.
• Fix transitive CVE-2023-43669 from tungstenite.

v0.20.0

Compare Source

• Change the buffering behavior for Sink::send() and Sink::feed(), see tungstenite's changelog for more details.

v0.19.0

Compare Source

• Allow users to enable/disable Nagle algorithm when using connect() helpers.
• Improve the behavior of the Sink for the WebSocketStream, so it does not return an error when it’s not necessary (when poll_flush() is called on a connection that has just been closed).
• Workaround an issue where rustls TLS backend expected domain in a certain format and reject IPv6 addresses if they contained square brackets in them.
• Update dependencies and remove unused errors.

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

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

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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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 Mend Renovate. View repository job log here.

[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 tokio-tungstenite@0.18.0 --precise 0.21.0
    Updating crates.io index
error: failed to select a version for the requirement `tokio-tungstenite = "^0.18"`
candidate versions found which didn't match: 0.21.0
location searched: crates.io index
required by package `kble-socket v0.2.0`
    ... which satisfies dependency `kble-socket = "^0.2.0"` (locked to 0.2.0) of package `kble-c2a v0.3.0-beta.1 (/tmp/renovate/repos/github/arkedge/kble/kble-c2a)`
perhaps a crate was updated and forgotten to be re-vendored?

[sksat]

Probably, the cargo update command for workspace dependencies is not working properly, and Renovate is throwing an artifact update problem: #34 (comment)

In practical use, this update can be used to build, and confirmed to work.