Uncomment updateMenuVisibility in index after making menu-toggle anim. work on first load

[marcus-grant]

The sidebar should default to being visible when a single preview card or max article width plus the sidebar width can fit.
But, right now when the MenuToggle component first loads it loads after everything else and thus tries to animate itself and it looks strange when it happens on the first load. Figure out how to make this work correctly and then uncomment updateMenuVisibility in src/layouts/index.js to return the page width default for an open menu.

[marcus-grant]

Here's a good link to learn about how to change state by using event listeners for page width
https://www.hawatel.com/blog/handle-window-resize-in-react/