fix: code blocks in email routing changelog (#21522)

Author: Cherry

src/content/changelog/email-routing/2025-04-08-local-development.mdx

@@ -19,6 +19,7 @@ export default {
 		console.log(email);
 	},
 };
+```
 
 Now when you run `npx wrangler dev`, wrangler will expose a local `/cdn-cgi/handler/email` endpoint that you can `POST` email messages to and trigger your Worker's `email()` handler:
 
@@ -74,4 +75,4 @@ This is what you get in the console:
 }
 ```
 
-Local development is a critical part of the development flow, and also works for sending, replying and forwarding emails. See [our documentation](/email-routing/email-workers/local-development/) for more information.
+Local development is a critical part of the development flow, and also works for sending, replying and forwarding emails. See [our documentation](/email-routing/email-workers/local-development/) for more information.