fix(lang/rust): typo

Co-authored-by: Kate Goldenring <[email protected]>

Author: vados-cosmonic

component-model/src/language-support/rust.md

@@ -145,7 +145,7 @@ Your code should look something like the following:
 
 There are a few points of note in the code listing above:
 
-- The `AdderComponent` struct si introduced, but is only useful as an implementer of the `Guest` trait.
+- The `AdderComponent` struct is introduced, but is only useful as an implementer of the `Guest` trait.
 - The `bindings::exports::docs::adder::add::Guest` trait mirrors the `docs:adder/add` interface
 - Our `AdderComponent` implements (in both the Rust sense and the WIT sense) the
 - The [`export!()` macro][export-macro] is generated by `wit_bindgen::generate!` macro, and does important setup