Enable focusing tabs by mouse scrolling on the tab row

https://code.visualstudio.com/updates/v1_45#_switch-tabs-using-mouse-wheel

When you use the mouse wheel to scroll over editor tabs, you currently cannot switch tabs, only reveal tabs that are out of view. Now with a new setting workbench.editor.scrollToSwitchTabs, you can change the behavior to switch the active editor tab.

Below when the cursor focus in the editor tab region, if the user scrolls their mouse wheel, the active editor changes.

Note: You can also press and hold the Shift key while scrolling to get the opposite behavior (for example, you can switch editor tabs even when the scrollToSwitchTabs setting is off).

This seemed like a cool idea, so I figured I'd add it here.