* fixed#1953 italic detection error
fix: issue where when html2md parse <em> to "_" instead of "*" that won't be detected MarkdownToDelta converter
feat(test): added test for DeltaX
feat: added config classes to MarkdownToDelta and html2md that allow users configure their own styles
* Added support for html underline and videos
* removed print calls and fix no expect in test
* removed useless element attr for underline
* improved video url validator pattern
* Added support for <video> tag
* chore: dart fixes
* fix: removed useless params
* fix: imports issue
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Co-authored-by: CatHood0 <santiagowmar@gmail.com>