Enable link to TNS book

components/custom-ad.tsx

@@ -1,5 +1,4 @@
 import { Box, Flex, Heading, Image, Link } from '@chakra-ui/react';
-import { getParameterByName } from '../pages/upcoming';
 
 function getPageSlug() {
   const pathname = (typeof window !== 'undefined' ? window : {} as any)?.location?.pathname || '';
@@ -13,11 +12,6 @@ export const CustomAd = () => {
     return null;
   }
 
-  const shouldShowAd = getParameterByName('ad');
-  if (!shouldShowAd) {
-    return null;
-  }
-
   return (
     <Link href='https://thenewstack.io/ebooks/devops/cloud-native-devops-2019/?utm_source=Roadmap&utm_medium=Banner&utm_campaign=DevOps+ebook' id='custom-ad' pos='fixed' bottom='15px' right='20px' zIndex={999} display='flex' maxWidth='330px'
           bg='white' boxShadow='0 1px 4px 1px hsla(0, 0%, 0%, .1)' _hover={{ textDecoration: 'none' }} rel="noopener sponsored">