Add a feature to Change User Email Address

[vrundraval24]

🚀 The feature

Users will be able to change their email address. and the next time they login they will be able to use updated email address.

Motivation, pitch

It is good to have this functionality when user is frequently using some other email and want to use that email in our app also. So they can manage things easily.

I am currently working on this issue. So, @chandansgowda please assign it to me.