maxPage property Null safety

1. nyxx_pagination
2. nyxx_pagination
3. SimpleComponentPagination
4. maxPage property

SimpleComponentPagination class

1. Constructors
2. SimpleComponentPagination
3. Properties
4. builder
5. contentPages
6. currentPage
7. customPreId
8. firstEmoji
9. firstLabel
10. hashCode
11. interactions
12. lastEmoji
13. lastLabel
14. maxPage
15. message
16. nextEmoji
17. nextLabel
18. prevEmoji
19. prevLabel
20. runtimeType
21. timeout
22. user
23. Methods
24. getMessageBuilderForPage
25. initHook
26. initMessageBuilder
27. noSuchMethod
28. onFirstPageButtonClicked
29. onLastPageButtonClicked
30. onNextPageButtonClicked
31. onPreviousPageButtonClicked
32. toString
33. updatePage
34. Operators
35. operator ==