Do some type changes and cleanup

[mdumandag]

• Changed the return type of geosearch commands from typed-dict to dataclass, to make it easier to use. Also, it conveys the optionality of the fields better now.
• Changed return types of sdiff, sunion, sinter, and smembers method to list from set. This eliminates extra set allocation for users doing iteration over the result. If they want, they can return the list into set themselves.
• Removed poetry.lock from the repo. We are a library, and the lock file will not be considered at all when the users install our library. If there is a problem in on of our depdencies during install, we would not be able to detect it at all due to lock file.
• Also applied isort and black into the codebase.