fix trailing ]

Author: MatthewPeterKelly

compiler/rustc_error_codes/src/error_codes/E0311.md

@@ -16,7 +16,7 @@ fn with_restriction<'a, T: 'a>(x: &'a ()) -> &'a () {
 Why doesn't this code compile? It helps to look at the lifetime bounds that are
 automatically adding by the compiler. For more details see the Rust
 Documentation for Lifetime Elision:
-https://doc.rust-lang.org/reference/lifetime-elision.html]
+https://doc.rust-lang.org/reference/lifetime-elision.html.
 
 There are two lifetimes being passed into the `no_restriction()` function: one
 associated with the generic type `T` parameter and the other with the input