Add missing "```"

GuillaumeGomez · GuillaumeGomez · commit 3c76163e1dc4 · 2015-07-07T19:37:54.000+02:00
diff --git a/src/librustc_typeck/diagnostics.rs b/src/librustc_typeck/diagnostics.rs
@@ -1467,6 +1467,7 @@ impl Foo for Bar {
     // the impl
     fn foo() {}
 }
+```
 "##,
 
 E0192: r##"
