[ListItem] Make `clickable` prop optional when `onClick` is defined

Make the clickable prop of the component ListItem optional if the onClick prop is defined.

-<ListItem clickable={condition} onClick={handleClick} />
+<ListItem onClick={condition && handleClick} />

clickable can still be used when onClick is not defined :

<ListItem clickable component='a' href='...' />

But clickable will be ignored if onClick is defined :

<ListItem clickable={false} onClick={handleClick} />

=> will be clickable anyway because onClick is defined