Nudges Serde to deserialise into fully owned ('static) instances where this is possible.

This is primarily useful when you have a structure that can optionally borrow the input (Think Cow<str> or Cow<[u8]>.), but a deserialiser that requires DeserializeOwned (which unfortunately seems to be common).

Deserialising borrow-only types (like plain references) naturally leads to a runtime error with this method.

Example

Given:

use {
    serde_detach::detach,
    serde_object::Object,
    serde_taml::de::from_str,
};

let input = "key: \"value\"".to_string();

This does not compile, since Object tries to borrow from the input:

let object: Object<'static> = from_str(&input, &mut ())?;
//          ---------------            ^^^^^^ borrowed value does not live long enough
//          |
//          type annotation requires that `input` is borrowed for `'static`

This works:

let object: Object<'static> = from_str(&input, &mut ()).map(detach)?;