2587: Absolute import of `Result` in derive r=syrusakbary a=ureeves

# Description

When aliasing `Result` deriving `WasmerEnv` is not possible. See a minimal example of the problem below.

```rust
use wasmer::WasmerEnv;

struct Error;
type Result<T> = core::result::Result<T, Error>;

#[derive(WasmerEnv, Clone)]
struct MyEnv; // error[E0107] this type alias takes 1 generic
              // argument but 2 generic arguments were supplied
```

# Review

- [x] Add a short description of the change to the CHANGELOG.md file


Co-authored-by: Eduardo Leegwater Simões <[email protected]>