No next button on the tutorials page

[fkhan77]

Issue: the tutorials page has no next button leading to the next subpage

Proposed solution: Add the next button on the page above the "Help improve this page" section on the tutorials page which leads to the first sub-page, in this case, it would be the page structure page

[brianelton]

This is the pattern throughout the sub sections, where the previous and next buttons are only for within that sub section and don't move to the next sub section. we can consider changing this, but it would be a low priority for now.