Convert v5.x.x samples to typescript in documentation

Current Behavior

react-navigation v5.x.x has written in typescript but documentation samples are based on javascript. in some cases it's hard to guess what type must be used

for example, I don't know what type I should use for creating the navigationRef in this documentation

having the examples in typescript language would be a great help (especially for those like me that working with previous versions of react-navigation and going to migrate their codes, there are a lot of changes in both libraries and types and it's hard to find at least for me.)

Expected Behavior

having documentation examples in typescript language. (or even having a switch button in code sections to switch between typescript and javascript examples)

How to reproduce

just review the documentation website :)

Your Environment

I think it does not really matter for the feature request.