Update posts/2019-05-23-Rust-1.35.0.md

Author: Centril

posts/2019-05-23-Rust-1.35.0.md

@@ -52,7 +52,7 @@ The following code now works:
 
 ```rust
 fn foo(x: Box<dyn Fn(u8) -> u8>) -> Vec<u8> {
-    vec![1,2,3,4].into_iter().map(x).collect()
+    vec![1, 2, 3, 4].into_iter().map(x).collect()
 }
 ```