Update Rust crate pkg-config to 0.3.29 (#542)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [pkg-config](https://togithub.com/rust-lang/pkg-config-rs) |
build-dependencies | patch | `0.3.28` -> `0.3.29` |

---

### Release Notes

<details>
<summary>rust-lang/pkg-config-rs (pkg-config)</summary>

###
[`v0.3.29`](https://togithub.com/rust-lang/pkg-config-rs/blob/HEAD/CHANGELOG.md#0329---2024-01-17)

[Compare
Source](https://togithub.com/rust-lang/pkg-config-rs/compare/0.3.28...0.3.29)

##### Fixed

- Detection and usage of Windows static libraries
([#&#8203;154](https://togithub.com/rust-lang/pkg-config-rs/issues/154)).

- Passing `-Wl,-u` to the linker if specified in the pkg-config file
([#&#8203;154](https://togithub.com/rust-lang/pkg-config-rs/issues/154)).

</details>

---

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emulator/mgba-sys/Cargo.toml

@@ -16,5 +16,5 @@ exclude = [
 
 [build-dependencies]
 bindgen = "0.69"
-pkg-config = "0.3.28"
+pkg-config = "0.3.29"
 cmake = "0.1"