Merge #2876

2876: Full support for compressed (Gzip, Brotli, Zlib) API requests r=Kerollmops a=mou

# Pull Request

## Related issue
Fixes #2802 

## What does this PR do?
- Adds missed content-encoding support for streamed requests (documents)
- Adds additional tests to validate content-encoding support is in place
- Adds new tests to validate content-encoding support for previously existing code (built-in actix functionality for unmarshaling JSON payloads)

## PR checklist
Please check if your PR fulfills the following requirements:
- [x] Does this PR fix an existing issue, or have you listed the changes applied in the PR description (and why they are needed)?
- [x] Have you read the contributing guidelines?
- [x] Have you made sure that the title is accurate and descriptive of the changes?

Thank you so much for contributing to Meilisearch!

Co-authored-by: Andrey "MOU" Larionov <anlarionov@gmail.com>

meilisearch-http/src/extractors/payload.rs

@@ -1,13 +1,14 @@
 use std::pin::Pin;
 use std::task::{Context, Poll};
 
+use actix_http::encoding::Decoder as Decompress;
 use actix_web::error::PayloadError;
 use actix_web::{dev, web, FromRequest, HttpRequest};
 use futures::future::{ready, Ready};
 use futures::Stream;
 
 pub struct Payload {
-    payload: dev::Payload,
+    payload: Decompress<dev::Payload>,
     limit: usize,
 }
 
@@ -39,7 +40,7 @@ impl FromRequest for Payload {
             .map(|c| c.limit)
             .unwrap_or(PayloadConfig::default().limit);
         ready(Ok(Payload {
-            payload: payload.take(),
+            payload: Decompress::from_headers(payload.take(), req.headers()),
             limit,
         }))
     }