Fix #33819 and update ui test

src/test/compile-fail/issue-33819.rs

@@ -0,0 +1,9 @@
+fn main() {
+    let mut op = Some(2);
+    match op {
+        Some(ref v) => { let a = &mut v; },
+        //~^ ERROR:cannot borrow immutable
+        //~| use `ref mut v` here to make mutable
+        None => {},
+    }
+}

src/test/ui/mismatched_types/main.stderr

@@ -1,8 +1,10 @@
 error: mismatched types [--explain E0308]
   --> $DIR/main.rs:14:18
+   |>
 14 |>     let x: u32 = (
    |>                  ^ expected u32, found ()
 note: expected type `u32`
 note:    found type `()`
 
+
 error: aborting due to previous error