Suggest if let on let refutable binding

src/test/ui/refutable-pattern-errors.stderr

@@ -9,6 +9,13 @@ error[E0005]: refutable pattern in local binding: `(std::i32::MIN..=0i32, _)` an
    |
 LL |     let (1, (Some(1), 2..=3)) = (1, (None, 2));
    |         ^^^^^^^^^^^^^^^^^^^^^ patterns `(std::i32::MIN..=0i32, _)` and `(2i32..=std::i32::MAX, _)` not covered
+   |
+   = note: `let` bindings require an "irrefutable pattern", like a `struct` or an `enum` with only one variant
+   = note: for more information, visit https://doc.rust-lang.org/book/ch18-02-refutability.html
+help: you might want to use `if let` to ignore the variant that isn't matched
+   |
+LL |     if let (1, (Some(1), 2..=3)) = (1, (None, 2)) { /* */ }
+   |
 
 error: aborting due to 2 previous errors