Use TOML syntax that is less likely to cause confusing errors

Author: irvinebroque

src/content/docs/browser-rendering/get-started/screenshots.mdx

@@ -72,10 +72,12 @@ main = "src/index.js"
 compatibility_date = "2023-03-14"
 compatibility_flags = [ "nodejs_compat" ]
 
-browser = { binding = "MYBROWSER" }
-kv_namespaces = [
-  { binding = "BROWSER_KV_DEMO", id = "22cf855786094a88a6906f8edac425cd", preview_id = "e1f8b68b68d24381b57071445f96e623" }
-]
+[browser]
+binding = "MYBROWSER"
+
+[[kv_namespaces]]
+binding = "BROWSER_KV_DEMO"
+id = "22cf855786094a88a6906f8edac425cd"
 ```
 
 </WranglerConfig>