Update docs for new release

[Breakthrough]

For the CLI this needs to be more automated. TODOs:

• Add check in the docs builder that checks running docs/generate_cli_docs.py does not result in any changes
  • Error message must include how to fix it (e.g. run python docs/generate_cli_docs.py from the root PySceneDetect folder)
• Determine if we should replace the file docs/cli.rst with a placeholder that includes info on how to generate it

[Breakthrough]

Added a new Check Documentation Github action that ensures the CLI docs won't get stale. This means that the majority of the API and CLI docs are now automatically kept in sync with the source code. There are still some docs that need to be maintained, but this should be far less of a burden now to keep track of.