Remove django-registration-redux

[anubhakushwaha]

FEATURE REQUEST:

Description:
To keep things clean and in order, removal of django-registration-redux before creating a custom-registration model.

[vaibhavsingh97]

@tapasweni-pathak @anubhakushwaha @nikhita Do I have to remove test cases too?

[anubhakushwaha]

@vaibhavsingh97 I guess it makes no sense to have tests for something that has been removed, though even for custom registration we will have similar tests but for now it's advisable to keep things together i.e have unit tests for the functionality together in the same PR.

[vaibhavsingh97]

@anubhakushwaha I am removing test cases for now, we will add when we have custom-registration-model