Update actix-web crate to v4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actix-web (source)	dependencies	major	3.3.3 -> 4.0.0

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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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[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 4.5.1
    Updating crates.io index
error: failed to select a version for the requirement `actix-web = "^3.0.0"`
candidate versions found which didn't match: 4.5.1
location searched: crates.io index
required by package `actix-cors v0.3.0`
    ... which satisfies dependency `actix-cors = "^0.3.0"` (locked to 0.3.0) of package `ogn-web-gateway v0.1.0 (/tmp/renovate/repos/github/Turbo87/ogn-web-gateway)`
perhaps a crate was updated and forgotten to be re-vendored?