OpenAPI attribute appears to break named lifetimes in the route handler.

Basically what the title says. 😄

If I change to `#[openapi(skip)]`, it works just fine, so I think there is some problem occurring with how the attribute generates code. The error message is

```
use of undeclared lifetime name `'r`
```

So, it seems like the attribute may be stripping the named lifetime argument from the method definition.