Make regexp/no-dupe-disjunctions account for nested alternatives (#404)

* Removed usage of deprected isDisjointWith function

* Added partial parser

* Implemented nested subsets

* Added tests for nested subset

* Added nested prefix subsets

* Added tests for nested prefix subsets

* Added missing docs

* Improved deduping

* Update lib/rules/no-dupe-disjunctions.ts

Co-authored-by: Yosuke Ota <[email protected]>

* Fixed linting error

* Fixed and documented optimization

* Added failing tests for bug

* Fixed incorrect partial NFA construction

* Fixed capturing group warning for nested alternatives

* Proper message escaping

* Improved messages

* Don't repeat the loc code

Co-authored-by: Yosuke Ota <[email protected]>

Author: RunDevelopment