Merge #3505

3505: Csv delimiter r=irevoire a=irevoire

Fixes https://github.com/meilisearch/meilisearch/issues/3442
Closes https://github.com/meilisearch/meilisearch/pull/2803
Specified in https://github.com/meilisearch/specifications/pull/221

This PR is a reimplementation of https://github.com/meilisearch/meilisearch/pull/2803, on the new engine. Thanks for your idea and initial PR `@MixusMinimax;` sorry I couldn’t update/merge your PR. Way too many changes happened on the engine in the meantime.

**Attention to reviewer**; I had to update deserr to implement the support of deserializing `char`s

-------

It introduces four new error messages;
- Invalid value in parameter csvDelimiter: expected a string of one character, but found an empty string
- Invalid value in parameter csvDelimiter: expected a string of one character, but found the following string of 5 characters: doggo
- csv delimiter must be an ascii character. Found: 🍰 
- The Content-Type application/json does not support the use of a csv delimiter. The csv delimiter can only be used with the Content-Type text/csv.

And one error code;
- `invalid_index_csv_delimiter`

The `invalid_content_type` error code is now also used when we encounter the `csvDelimiter` query parameter with a non-csv content type.

Co-authored-by: Tamo <tamo@meilisearch.com>

Cargo.lock

@@ -1113,9 +1113,9 @@ dependencies = [
 
 [[package]]
 name = "deserr"
-version = "0.4.1"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6eee2844f21cf7fb5693aae1fb8f1658127acfdb2fc072167d68a9152584ae64"
+checksum = "c71c14985c842bf1e520b1ebcd22daff6aeece32f510e11f063cecf9b308c04b"
 dependencies = [
  "actix-http",
  "actix-utils",
@@ -1130,9 +1130,9 @@ dependencies = [
 
 [[package]]
 name = "deserr-internal"
-version = "0.4.1"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c27246f8ca9eeba9dd70d614b664dc43b529251ed7bd9e633131010d340da4b9"
+checksum = "cae1c51b191528c9e4e5d6cff671de94f61fcda1c206cc891251e0cf438c941a"
 dependencies = [
  "convert_case 0.5.0",
  "proc-macro2",