Add doctests section

Author: BoxyUwU

content/Rust-1.89.0.md

@@ -132,9 +132,14 @@ pub fn cool_simd_code(/* .. */) -> /* ... */ {
 
 ```
 
+### Cross-compiled doctests
+
+Doctests will now be tested when running `cargo test --doc --target other_target`, this may result in some amount of breakage due to would-be-failing doctests now being tested.
+
 ### Platform Support
 
 - [Add new Tier-3 targets `loongarch32-unknown-none` and `loongarch32-unknown-none-softfloat`](https://github.com/rust-lang/rust/pull/142053)
+- [WASM's C abi is now spec compliant](https://github.com/rust-lang/rust/pull/133952)
 
 Refer to Rust’s [platform support page][platform_support_page] for more information on Rust’s tiered platform support.