* Add answer deduplication
* Fix test
* Handle None case
* Release notes
* Handle cases where documents or answer spans could be None
* Adding checks for Nones and satisfying mypy
* Add option to turn off deduplication
* Adding unit tests
* Refactored tests to use fixtures
* Added overlap_threshold to run
* Update test
* Fixes related to the merge
* Remove casting, use direct variable names
* Move out if statement and add new test for it
* Update if statement to match comment
* Update how if statements work
