Account for `!` arm in tail `match` expr

On functions with a default return type that influences the coerced type
of `match` arms, check if the failing arm is actually of type `!`. If
so, suggest changing the return type so the coercion against the prior
arms is successful.

```
error[E0308]: `match` arms have incompatible types
  --> $DIR/match-tail-expr-never-type-error.rs:9:13
   |
LL |   fn bar(a: bool) {
   |                  - help: try adding a return type: `-> i32`
LL | /     match a {
LL | |         true => 1,
   | |                 - this is found to be of type `{integer}`
LL | |         false => {
LL | |             never()
   | |             ^^^^^^^
   | |             |
   | |             expected integer, found `()`
   | |             this expression is of type `!`, but it get's coerced to `()` due to its surrounding expression
LL | |         }
LL | |     }
   | |_____- `match` arms have incompatible types
```

Fix #24157.

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