Partial document struct for updates

[RoDmitry]

Auto-generates a partial document struct for updates. To avoid serde_json::Value as an input.

#[derive(typesense::Typesense, Serialize, Deserialize, Debug, PartialEq, Clone)]
struct Book {
    id: String,
    title: String,
    author: String,
    publication_year: i32,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    in_stock: Option<bool>,
}
let partial_update_struct = BookPartial {
    publication_year: Some(1966),
    in_stock: Some(Some(false)),
    ..Default::default()
};
let updated_book = typed_collection
    .document(&book_1.id)
    .update(&partial_update_struct, None)
    .await
    .expect("Failed to update typed document");

Derive macro creates struct BookPartial with all optional fields.

@haydenhoang what do you think? Need help with deciding about collection_schemaless tests (in typesense/tests/client/documents_test.rs). Do you need collection_schemaless updates and creates? As you know I hate serde_json::Value. Is there any point in implementing it?

Also I don't know if id is updatable.
And is there a reason to have Option<Option<bool>> for updates, or should it be Option<bool>?