⬆️ micro: Update serde to v1.0.217 (#1191)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [serde](https://serde.rs)
([source](https://redirect.github.com/serde-rs/serde)) | dependencies |
patch | `1.0.216` -> `1.0.217` |
| [serde](https://serde.rs)
([source](https://redirect.github.com/serde-rs/serde)) |
dev-dependencies | patch | `1.0.216` -> `1.0.217` |

---

### Release Notes

<details>
<summary>serde-rs/serde (serde)</summary>

###
[`v1.0.217`](https://redirect.github.com/serde-rs/serde/releases/tag/v1.0.217)

[Compare
Source](https://redirect.github.com/serde-rs/serde/compare/v1.0.216...v1.0.217)

- Support serializing externally tagged unit variant inside flattened
field
([#&#8203;2786](https://redirect.github.com/serde-rs/serde/issues/2786),
thanks [@&#8203;Mingun](https://redirect.github.com/Mingun))

</details>

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