website: try to fix SSR mismatch bug

website/src/components/SidebarAd/index.js

@@ -21,6 +21,7 @@ export default React.memo(function SidebarAd() {
     <a
       className={clsx(styles.container, backgroundClass)}
       href="https://www.moonchaser.io/?utm_source=techinterviewhandbook&utm_medium=referral&utm_content=website_docs_sidebar"
+      key={Math.random()}
       target="_blank"
       rel="noreferrer noopener"
       onClick={() => {
@@ -35,6 +36,7 @@ export default React.memo(function SidebarAd() {
     <a
       className={clsx(styles.container, backgroundClass)}
       href="https://www.levels.fyi/services/?ref=TechInterviewHandbook&utm_source=techinterviewhandbook&utm_medium=referral&utm_content=website_docs_sidebar"
+      key={Math.random()}
       target="_blank"
       rel="noreferrer noopener"
       onClick={() => {

website/src/pages/index.js

@@ -64,7 +64,7 @@ function Home() {
               <div className="col col--8 col--offset-2">
                 <div className="margin-vert--lg text--center">
                   {Math.random() > 0.5 ? (
-                    <>
+                    <div key={Math.random()}>
                       <h2 className={styles.sectionPrimaryTitle}>
                         <strong>
                           Get paid more. Receive risk-free salary negotiation
@@ -84,9 +84,9 @@ function Home() {
                           Get Risk-free Negotiation Help&nbsp;&nbsp;→
                         </a>
                       </div>
-                    </>
+                    </div>
                   ) : (
-                    <>
+                    <div key={Math.random()}>
                       <h2 className={styles.sectionPrimaryTitle}>
                         <strong>
                           Get paid, not played. Chat with former tech recruiters
@@ -106,7 +106,7 @@ function Home() {
                           Get Negotiation Help&nbsp;&nbsp;→
                         </a>
                       </div>
-                    </>
+                    </div>
                   )}
                 </div>
               </div>