Remove register_feed because it duplicates register_asset_feed

[yordanmadzhunkov]

Currently in apps/sequencer/src/http_handlers/data_feeds.rs

#[post("/feed/register")]
pub async fn register_feed(
    register_request: web::Json<RegisterFeedRequest>,
    sequencer_state: web::Data<SequencerState>,
) -> Result<HttpResponse, Error> {

This method is exposed as endpoint and mostly written by Delyan. There is same functionality

#[post("/register_asset_feed")]
pub async fn register_asset_feed(
    mut payload: web::Payload,
    sequencer_state: web::Data<SequencerState>,
) -> Result<HttpResponse, Error> {

Both of them have corresponding tests and one of them must be removed.

I think register_feed is more outdated and we should delete it.