chore(deps): update msrv (3 versions) to v1.91 (#16587)

This PR contains the following updates:

| Package | Update | Change | Pending |
|---|---|---|---|
| [MSRV:3](https://redirect.github.com/rust-lang/rust) | minor | `1.90`
→ `1.91` | `1.93` (+1) |

---

### Release Notes

<details>
<summary>rust-lang/rust (MSRV:3)</summary>

###
[`v1.91`](https://redirect.github.com/rust-lang/rust/blob/HEAD/RELEASES.md#Version-1911-2025-11-10)

[Compare
Source](https://redirect.github.com/rust-lang/rust/compare/1.90.0...1.91.0)

\===========================

<a id="1.91.1"></a>

- [Enable file locking support in
illumos](https://redirect.github.com/rust-lang/rust/pull/148322). This
fixes Cargo not locking the build directory on illumos.
- [Fix `wasm_import_module` attribute
cross-crate](https://redirect.github.com/rust-lang/rust/pull/148363).
This fixes linker errors on WASM targets.

</details>

---

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Author: ehuss

Cargo.toml

@@ -11,7 +11,7 @@ exclude = [
 ]
 
 [workspace.package]
-rust-version = "1.90"  # MSRV:3
+rust-version = "1.91"  # MSRV:3
 edition = "2024"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/rust-lang/cargo"