BUG: No alert saying 'you are subscribed' is showing up on entering mail in footer section

[divyalaldinani]

Is there an existing issue for this?

• [X] I have searched the existing issues

What happened?

There's no alert box showing up if someone enters mail, or there's no check if mail is valid or not. Thus, first we should add regex checker to check for validity of mail and then show an alert box if user submits a valid mail.

Record

• [X] I agree to follow this project's Code of Conduct
• [X] I'm a GSSOC'24 contributor
• [X] I want to work on this issue