Rollup merge of #34014 - GuillaumeGomez:fix-E0165, r=jonathandturner

Fix E0165 code examples

r? @steveklabnik

Author: GuillaumeGomez

src/librustc_const_eval/diagnostics.rs

@@ -384,18 +384,19 @@ let irr = Irrefutable(0);
 
 // This fails to compile because the match is irrefutable.
 while let Irrefutable(x) = irr {
-    ...
+    // ...
 }
+```
 
 Try this instead:
 
-```
+```no_run
 struct Irrefutable(i32);
 let irr = Irrefutable(0);
 
 loop {
     let Irrefutable(x) = irr;
-    ...
+    // ...
 }
 ```
 "##,

src/librustc_typeck/diagnostics.rs

@@ -2040,6 +2040,7 @@ impl Foo for Bar {
     // the trait
     fn foo(&self) {}
 }
+```
 "##,
 
 E0186: r##"