Replace data table in dl_read_gcp

[biodavidjm]

Replace data table by read_delim from readx

  if(file.exists(new_path)) {
    df <- readr ::read_delim(new_path, delim = sep, col_names = header, ...)
    return(df)
  } else {
    stop("- Problems loading the file. Possible reason: the file does not exist in the bucket anymore. Please, validate the address. Re-run this command again with `verbose = TRUE`)")
  }

[biodavidjm]

Same as #227