Fix capitalization of Rust (#1007)

src/basic-syntax/methods.md

@@ -39,7 +39,7 @@ fn main() {
     }
     ```
 
-- While _technically_, rust does not have custom constructors, static methods are commonly used to initialize structs (but don't have to).
+- While _technically_, Rust does not have custom constructors, static methods are commonly used to initialize structs (but don't have to).
   The actual constructor, `Rectangle { width, height }`, could be called directly. See the [Rustnomicon](https://doc.rust-lang.org/nomicon/constructors.html).
 
 - Add a `Rectangle::new_square(width: u32)` constructor to illustrate that such static methods can take arbitrary parameters.