Update Rust crate mdbook to v0.4.45 (#25193)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [mdbook](https://redirect.github.com/rust-lang/mdBook) | dependencies
| patch | `0.4.44` -> `0.4.45` |

---

### Release Notes

<details>
<summary>rust-lang/mdBook (mdbook)</summary>

###
[`v0.4.45`](https://redirect.github.com/rust-lang/mdBook/blob/HEAD/CHANGELOG.md#mdBook-0445)

[Compare
Source](https://redirect.github.com/rust-lang/mdBook/compare/v0.4.44...v0.4.45)


[v0.4.44...v0.4.45](https://redirect.github.com/rust-lang/mdBook/compare/v0.4.44...v0.4.45)

##### Changed

-   Added context to error message when rustdoc is not found.
[#&#8203;2545](https://redirect.github.com/rust-lang/mdBook/pull/2545)
-   Slightly changed the styling rules around margins of footnotes.
[#&#8203;2524](https://redirect.github.com/rust-lang/mdBook/pull/2524)

##### Fixed

-   Fixed an issue where it would panic if a source_path is not set.
[#&#8203;2550](https://redirect.github.com/rust-lang/mdBook/pull/2550)

</details>

---

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Release Notes:

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