New lint that detects when `fetch_update` was used when `update` would suffice.

### What it does

This makes sense only when https://github.com/rust-lang/rust/pull/133829 has been stabilized.

### Advantage

_No response_

### Drawbacks

_No response_

### Example

```rust
<code>
```

Could be written as:

```rust
<code>
```
