[Feat]: Add Confirmation Message and Check Mark on Newsletter Subscription

[AdityaP700]

What feature?

Description

When a user clicks the "Subscribe" button in the newsletter section, the system should display a confirmation message, along with a check mark, to notify the user that they have successfully subscribed. This will improve user feedback and enhance the subscription experience.
UI Changes:

Overview

Once the "Subscribe" button is clicked, replace the button text with a confirmation message such as: “You are subscribed! ✅”.
or changing the button style (color, background) to visually indicate that the user has successfully subscribed.

Add screenshots

Add screenshots

Code of Conduct

• I agree to follow this project's Code of Conduct

[AdityaP700]

Kindly Look into the issue and let me assign to work on this issue under GSSOC-extd and HackOctoberFest tag under any Level . Thanks in Anticipation :)

[RohithNair27]

Hello. I am new and would love to contribute.
I would like to add this enhancement, if no one is already on it.

[ishap11]

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