Pybit

Added
- Multiple symbol support for WebSocket topics (pass `symbol` as a list)
- Extra logging (log response headers) when passing `log_requests=True`
- Argument `return_response_headers` for `HTTP` to allow returning the response headers to the user

Modified
- Add response headers to exceptions

Fixed
- Update PyPI package's python version so that only =>3.9 is supported to prevent the error: `TypeError: 'type' object is not subscriptable`
- Fix API rate limit handling
- Remove unnecessary `print` statements in two methods

Added
- New asset endpoints: `set_deposit_account()`, `get_internal_deposit_records()`, `get_withdrawable_amount()`

Fixed
- Ensure that `legacy` submodule is packaged by `setup.py`
- Fix non-UTA (normal account) spot margin trading endpoints
- Fix wrong request method for `set_dcp()`

Added
- HTTP endpoints to the `copy_trading` module

Modified
- Docstrings in the `copy_trading` module to make it easier to find the API documentation for reference
- Example files

Fixed
- `ticker_stream` method in the `unified_trading` module, which was subscribing to the wrong WebSocket topic

This version upgrades pybit to Bybit's [version 5 (v5) APIs](https://bybit-exchange.github.io/docs/v5/intro). It supports both [Unified Trading Accounts](https://www.bybit.com/en-US/help-center/s/article/Introduction-to-Bybit-Unified-Trading-Account) (UTA) and non-UTA accounts. Bybit is not expected to develop any more major API versions in the future, so Bybit's v5 API (and subsequently, pybit's 5.0.0) is expected to be supported in the long-term.

See the [examples folder](https://github.com/bybit-exchange/pybit/tree/master/examples) for examples on how to interact with the latest modules.

Added
- Bybit's v5 HTTP and WebSocket APIs in the `unified_trading` module. See what markets All-In-One V5 API supports in the [upgrade guide](https://bybit-exchange.github.io/docs/v5/upgrade-guide).

Modified
- Non-v5 modules like `copy_trading`, `usdc_options`, and `usdc_perpetuals` to continue to work from a `legacy` subpackage. Import like so: `from pybit.legacy.copy_trading import HTTP
`. These modules are maintained because they are currently not supported by the v5 API; see the [upgrade guide](https://bybit-exchange.github.io/docs/v5/upgrade-guide).

Removed
- Various legacy modules which have been superseded by the v5 API via the `unified_trading` module

Fixed
- Tests for V5 endpoints

Added
- `copy_trading` module for the [Copy Trading](https://bybit-exchange.github.io/docs/copy_trading/) HTTP API and WebSocket

Modified
- `requirements.txt` to require the latest version of `websocket-client`: `1.5.0`.
- If you are facing any problems with the WebSocket, ensure you upgrade to the right version of the dependency and try again. Upgrade like so: `python -m pip install -r requirements.txt`
- WebSocket pings (again)

Modified
- How WebSocket pings are sent in an effort to keep connections open longer