[ext.pages] Add ability to specify in which row the paginator buttons are displayed

[krittick]

Summary

This adds the missing row parameter to PaginatorButton to allow users to have more control over which rows their paginator buttons display in.

This also adds a new parameter default_button_row which controls the same behavior for the default set of paginator buttons.

Checklist

• If code changes were made then they have been tested.
  • I have updated the documentation to reflect the changes.
• If type: ignore comments were used, a comment is also left explaining why
• This PR fixes an issue.
• This PR adds something new (e.g. new method or parameters).
• This PR is a breaking change (e.g. methods or parameters removed/renamed)
• This PR is not a code change (e.g. documentation, README, typehinting, examples, ...)

[Dorukyum]

Shouldn't the type just be int since it's defaulted to 0?

[krittick]

Shouldn't the type just be int since it's defaulted to 0?

Good catch, updated.