change 3rd party scripts to defer

src/pages/_app.tsx

@@ -181,7 +181,7 @@ function MyApp({ Component, pageProps }) {
         <>
           <script
             src="https://aa0.awsstatic.com/s_code/js/3.0/awshome_s_code.js"
-            async
+            defer
           ></script>
           <script
             src="https://alpha.d2c.marketing.aws.dev/client/loader/v1/d2c-load.js"
@@ -192,7 +192,7 @@ function MyApp({ Component, pageProps }) {
         <>
           <script
             src="https://a0.awsstatic.com/s_code/js/3.0/awshome_s_code.js"
-            async
+            defer
           ></script>
           <script
             src="https://d2c.aws.amazon.com/client/loader/v1/d2c-load.js"

src/pages/_document.tsx

@@ -130,7 +130,7 @@ export default class MyDocument extends Document {
           />
           <script
             src="https://prod.assets.shortbread.aws.dev/shortbread.js"
-            async
+            defer
           ></script>
           <link
             href="https://prod.assets.shortbread.aws.dev/shortbread.css"