[FEAT] Scroll to top button in documentation pages

[xelaint]

:bulb: Feature request

Feature Name

Scroll to top button in documentation pages

The Desired Behavior

Add a scroll to top button on the bottom right corner of all documentation pages.

Your Use Case

As a user, I would like an easy way to scroll back to the top, especially if the documentation page is very long.

Prior Work

Environment

Daffodil version: X.Y.Z
Angular version: X.Y.Z 

 
For Tooling issues:
- Node version: XX  
- Platform:  

Others: