Fix search activation when no query is present
Fix search activation when no query is present

Closes #661, as pointed out by @birjolaxew the return value by
getUrlParameter() will not be null but an empty string (which is a falsy
value) if no query is present, checking for truthiness should work
correctly.

danleech/simpleicons.org,simple-icons/simple-icons,birjolaxew/simple-icons,danleech/simple-icons,birjolaxew/simple-icons,simple-icons/simple-icons,danleech/simpleicons.org