ENHANCEMENT: Show Newsletter Subscription Confirmation message

### Description:
We need to enhance the user experience by displaying a clear and user-friendly confirmation message after successful subscription to our newsletter. This will inform users that their subscription was successful and that they will start receiving updates from us.

### Expected Behavior:
After submitting the email on the newsletter sign-up form, users should see a confirmation message.
The message should appear on the same page without redirecting the user.

Kindly assign me this issue