DOC: Fixes to Accelerator docstring (#2443)
* DOC Fixes to Accelerator docstring
- Add more links to accelerator classes where applicable
- Fix a typo: KwargHandler => KwargsHandler
* Fix syntax issues
Not sure how to add a link of the type is `list[SomeType]`, so just
removed it for now.
* Fixing link for KwargsHandler
* Add KwargsHandler to API docs
* Also add doc entry to kwargs.md
