Rollup merge of #101165 - ldm0:drain_to_iter, r=cjgillot

Use more `into_iter` rather than `drain(..)`

Clearer semantic.

compiler/rustc_macros/src/diagnostics/diagnostic_builder.rs

@@ -239,7 +239,7 @@ impl DiagnosticDeriveBuilder {
             }
         }
 
-        Ok(tokens.drain(..).collect())
+        Ok(tokens.into_iter().collect())
     }
 
     fn generate_field_attrs_code(&mut self, binding_info: &BindingInfo<'_>) -> TokenStream {