[docs] Add material-ui-flat-pagination to related projects (#17372)

docs/src/pages/discover-more/related-projects/related-projects.md

@@ -46,6 +46,10 @@ They support many different use cases (editable, filtering, grouping, sorting, s
 
 - [material-ui-image](https://mui.wertarbyte.com/#material-ui-image): Images are ugly until they're loaded. Materialize it with material image! It will fade in like the material image loading pattern suggests.
 
+### Pagination
+
+- [material-ui-flat-pagination](https://github.com/szmslab/material-ui-flat-pagination): A flat design pagination component for Material-UI.
+
 ## Theming
 
 - [create-mui-theme](https://react-theming.github.io/create-mui-theme/): An online tool for creating Material-UI themes via Material Design Color Tool.