chore(deps): update rust crate protobuf to v3.5.1 (#118)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [protobuf](https://redirect.github.com/stepancheg/rust-protobuf) |
dev-dependencies | patch | `3.5.0` -> `3.5.1` |

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### Release Notes

<details>
<summary>stepancheg/rust-protobuf (protobuf)</summary>

###
[`v3.5.1`](https://redirect.github.com/stepancheg/rust-protobuf/blob/HEAD/CHANGELOG.md#351---Unreleased)

[Compare
Source](https://redirect.github.com/stepancheg/rust-protobuf/compare/v3.5.0...v3.5.1)

- [Remove deprecated `box_pointers`
lint](https://redirect.github.com/stepancheg/rust-protobuf/pull/733)

</details>

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