Update dependency express to v4.21.1 (#40)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [express](http://expressjs.com/) ([source](https://redirect.github.com/expressjs/express)) | [`4.21.0` -> `4.21.1`](https://renovatebot.com/diffs/npm/express/4.21.0/4.21.1) | [![age](https://developer.mend.io/api/mc/badges/age/npm/express/4.21.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://developer.mend.io/api/mc/badges/adoption/npm/express/4.21.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://developer.mend.io/api/mc/badges/compatibility/npm/express/4.21.0/4.21.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://developer.mend.io/api/mc/badges/confidence/npm/express/4.21.0/4.21.1?slim=true)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>expressjs/express (express)</summary>

### [`v4.21.1`](https://redirect.github.com/expressjs/express/compare/4.21.0...8e229f92752ad51462c868b99f6e6c2e559801b0)

[Compare Source](https://redirect.github.com/expressjs/express/compare/4.21.0...4.21.1)

</details>

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