seo: fix page has links to redirect (#708)

Co-authored-by: Yangshun Tay <tay.yang.shun@gmail.com>

apps/website/src/components/SidebarAd/index.js

@@ -95,7 +95,7 @@ function DesignGurusSystemDesign({ position }) {
   return (
     <a
       className={clsx(styles.container, styles.backgroundGrokkingSystemDesign)}
-      href="https://designgurus.org/link/kJSIoU?url=https%3A%2F%2Fdesigngurus.org%2Fcourse%3Fcourseid%3Dgrokking-the-system-design-interview"
+      href="https://www.designgurus.io/course/grokking-the-system-design-interview?aff=kJSIoU"
       key={Math.random()}
       target="_blank"
       rel="noopener"

apps/website/src/data/successStories.js

@@ -58,8 +58,8 @@ export default [
         <br />
         <br />
         I've learnt a few things and blogged about them on{' '}
-        <a href="https://zhenghao.io" rel="noopener">
-          https://zhenghao.io
+        <a href="https://www.zhenghao.io/" rel="noopener">
+          https://www.zhenghao.io/
         </a>
         , check them out if you're interested!
       </>
@@ -153,7 +153,7 @@ export default [
         <br />
         My favourite part is the{' '}
         <a
-          href="https://www.techinterviewhandbook.org/grind75"
+          href="https://www.techinterviewhandbook.org/grind75/"
           target="_blank"
           rel="noreferrer noopener">
           Grind 75 Tool

apps/website/src/pages/index.js

@@ -492,7 +492,7 @@ function GreatFrontEndSection() {
                 <div className="margin-vert--lg">
                   <a
                     className="button button--secondary button--lg"
-                    href="https://www.greatfrontend.com/prepare?fpr=yangshun&utm_source=techinterviewhandbook&utm_medium=referral&utm_content=homepage"
+                    href="https://www.greatfrontend.com/questions?fpr=yangshun&utm_source=techinterviewhandbook&utm_medium=referral&utm_content=homepage"
                     rel="noopener"
                     target="_blank"
                     onClick={() => {