YahooFinanceProcessor.scrap_data sorts by a missing tick column

## Bug

`YahooFinanceProcessor.scrap_data()` raises `KeyError: "tick"` after successfully combining downloaded frames.

## Reproduction

Stub `fetch_stock_data()` to return frames containing the columns produced by the implementation, including `day` and `tic`, then call `scrap_data()` for two symbols. The final `sort_values()` call fails because it requests `tick`.

## Cause

`fetch_stock_data()` creates a `tic` column, while `scrap_data()` sorts by `["day", "tick"]`.

## Expected behavior

The combined frame should sort by `day` and `tic` and return normally.