Bump websockets from 8.1 to 9.1

Bumps [websockets](https://github.com/aaugustin/websockets) from 8.1 to 9.1.
- [Release notes](https://github.com/aaugustin/websockets/releases)
- [Changelog](https://github.com/aaugustin/websockets/blob/9.1/docs/changelog.rst)
- [Commits](python-websockets/websockets@8.1...9.1)

Signed-off-by: dependabot[bot] <support@github.com>

requirements.txt

@@ -8,4 +8,4 @@ requests
 ujson
 unicorn-fy
 websocket-client
-websockets==8.1
+websockets==9.1

setup.py

@@ -52,7 +52,7 @@
      long_description=long_description,
      long_description_content_type="text/markdown",
      license='MIT License',
-     install_requires=['colorama', 'pathlib', 'requests', 'websocket-client', 'websockets==8.1', 'flask_restful',
+     install_requires=['colorama', 'pathlib', 'requests', 'websocket-client', 'websockets==9.1', 'flask_restful',
                        'cheroot', 'flask', 'ujson', 'psutil', 'unicorn-fy'],
      keywords='binance, asyncio, async, asynchronous, concurrent, websocket-api, webstream-api, '
               'binance-websocket, binance-webstream, webstream, websocket, api, binance-jersey, binance-dex, '