Add aria-controls attribute to drawer activator

The drawer activator should contain an aria-controls attribute referencing the drawer panel to highlight the fact that the drawer presence is controlled by the activator.
 
References:

• https://www.w3.org/TR/wai-aria-1.1/#aria-controls
• https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/Roles/Tab_Role
• https://tink.uk/using-the-aria-controls-attribute/

See also the aria-owns attribute:

• https://stackoverflow.com/questions/34003530/what-is-the-difference-between-aria-owns-and-aria-controls