remove unused registration templates

lms/templates/registration/change_password.html

lms/templates/registration/logged_out.html

lms/templates/registration/login.html

lms/templates/registration/login_error.html

lms/templates/registration/logout.html

lms/templates/registration/password_change_done.html

lms/templates/registration/password_change_form.html

lms/templates/registration/registration_complete.html

lms/templates/registration/registration_form.html