More move error suggestions to clone

```
error[E0507]: cannot move out of `val`, a captured variable in an `FnMut` closure
  --> $DIR/issue-87456-point-to-closure.rs:10:28
   |
LL |     let val = String::new();
   |         --- captured outer variable
LL |
LL |     take_mut(|| {
   |              -- captured by this `FnMut` closure
LL |
LL |         let _foo: String = val;
   |                            ^^^ move occurs because `val` has type `String`, which does not implement the `Copy` trait
   |
help: consider borrowing here
   |
LL |         let _foo: String = &val;
   |                            +
help: consider cloning the value if the performance cost is acceptable
   |
LL |         let _foo: String = val.clone();
   |                               ++++++++
```

compiler/rustc_borrowck/src/diagnostics/move_errors.rs

@@ -444,6 +444,10 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                         None => "value".to_string(),
                     };
 
+                    if let Some(expr) = self.find_expr(span) {
+                        self.suggest_cloning(err, place_ty, expr, span);
+                    }
+
                     err.subdiagnostic(
                         self.dcx(),
                         crate::session_diagnostics::TypeNoCopy::Label {