Registration form: removed validation of Terms of Services when the checkbox is hidden

Background: Registration form with hidden checkbox "Terms of Services" still validates it (and an error message is displayed).

Studio Updates: None.

LMS Updates: Removed validation of the checkbox "Terms of Services" on the Registration form for the following settings in /edx/app/edxapp/lms.env.json:
"FEATURES" > "ENABLE_COMBINED_LOGIN_REGISTRATION" = true
"REGISTRATION_EXTRA_FIELDS" > 'honor_code' != 'required'

Manual test instructions:
1. update /edx/app/edxapp/lms.env.json settings
"FEATURES" > "ENABLE_COMBINED_LOGIN_REGISTRATION" = true
"REGISTRATION_EXTRA_FIELDS" > 'honor_code' != 'required'

2. Start LMS and go to http://127.0.0.1:8000/register and try to add a user filling in only required fields. You should add it successfully, no error message 'You must accept the terms of service' is displayed.