adjust import to avoid compilation errors

[saks]

Change the way we import traits in order to avoid compilation issues in some cases.

This issue was reported to serde (serde-rs/serde#1441) and can be avoided with suggested changes.

With the current code (version 0.1.0) it is impossible to compile lambda-http with some other crates (like https://github.com/mitsuhiko/insta).

Minimal example:

main.rs

use lambda_http::lambda;

fn main() {
    lambda!(|_, _| Ok(""));
}

Cargo.toml

[package]
name = "aws-lambda-http-bug"
version = "0.1.0"
authors = ["Aliaksandr Rahalevich <[email protected]>"]
edition = "2018"

[dependencies]
lambda_http = "0.1.0"
serde = { features = ["derive"] }

then compilation fails with:

   Compiling lambda_http v0.1.0
error[E0252]: the name `Deserialize` is defined multiple times
  --> /home/<USER>/.cargo/registry/src/github.amrom.workers.dev-1ecc6299db9ec823/lambda_http-0.1.0/src/request.rs:17:5
   |
15 |     Deserialize, Deserializer,
   |     ----------- previous import of the macro `Deserialize` here
16 | };
17 | use serde_derive::Deserialize;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ `Deserialize` reimported here
   |
   = note: `Deserialize` must be defined only once in the macro namespace of this module
help: you can use `as` to change the binding name of the import
   |
17 | use serde_derive::Deserialize as OtherDeserialize;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to previous error

For more information about this error, try `rustc --explain E0252`.
error: Could not compile `lambda_http`.

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[davidbarsky]

Ugh, hygiene. Thanks for the catch.

[arahalevich-move]

Thanks!