Typos

README.md

@@ -419,7 +419,7 @@ fn main() {
     let mut my_variable = 8;
     my_variable = "Hello, world!";
 }
-```rust
+```
 
 You will see the same "expected" message from the compiler: ```expected integer, found `&str```` (```&str``` is a string type that we will learn soon).