Update map_clone lint ui test

Author: GuillaumeGomez

tests/ui/useless_asref.fixed

@@ -132,6 +132,14 @@ fn generic_ok<U: AsMut<T> + AsRef<T> + ?Sized, T: Debug + ?Sized>(mru: &mut U) {
     foo_rt(mru.as_ref());
 }
 
+fn foo() {
+    let x = Some(String::new());
+    let y = x.as_ref().cloned();
+    //~^ ERROR: you are using an explicit closure for cloning elements
+    let y = x.as_ref().cloned();
+    //~^ ERROR: you are using an explicit closure for cloning elements
+}
+
 fn main() {
     not_ok();
     ok();

tests/ui/useless_asref.rs

@@ -132,6 +132,14 @@ fn generic_ok<U: AsMut<T> + AsRef<T> + ?Sized, T: Debug + ?Sized>(mru: &mut U) {
     foo_rt(mru.as_ref());
 }
 
+fn foo() {
+    let x = Some(String::new());
+    let y = x.as_ref().map(Clone::clone);
+    //~^ ERROR: you are using an explicit closure for cloning elements
+    let y = x.as_ref().map(String::clone);
+    //~^ ERROR: you are using an explicit closure for cloning elements
+}
+
 fn main() {
     not_ok();
     ok();

tests/ui/useless_asref.stderr

@@ -70,5 +70,20 @@ error: this call to `as_ref` does nothing
 LL |     foo_rt(mrt.as_ref());
    |            ^^^^^^^^^^^^ help: try: `mrt`
 
-error: aborting due to 11 previous errors
+error: you are using an explicit closure for cloning elements
+  --> $DIR/useless_asref.rs:137:13
+   |
+LL |     let y = x.as_ref().map(Clone::clone);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling the dedicated `cloned` method: `x.as_ref().cloned()`
+   |
+   = note: `-D clippy::map-clone` implied by `-D warnings`
+   = help: to override `-D warnings` add `#[allow(clippy::map_clone)]`
+
+error: you are using an explicit closure for cloning elements
+  --> $DIR/useless_asref.rs:139:13
+   |
+LL |     let y = x.as_ref().map(String::clone);
+   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider calling the dedicated `cloned` method: `x.as_ref().cloned()`
+
+error: aborting due to 13 previous errors