ISTWCMS-4725: removing config that is no longer needed so that config sync works

config/install/cas.settings.yml

-server:
-  version: '2.0'
-  hostname: cas.uwaterloo.ca
-  port: 443
-  path: /cas
-  verify: 0
-  cert: ''
-gateway:
-  check_frequency: -2
-  paths:
-    id: request_path
-    pages: ''
-    negate: false
-forced_login:
-  enabled: false
-  paths:
-    id: request_path
-    pages: ''
-    negate: false
-logout:
-  logout_destination: ''
-  enable_single_logout: false
-  cas_logout: false
-  single_logout_session_lifetime: 25
-proxy:
-  initialize: false
-  can_be_proxied: false
-  proxy_chains: ''
-user_accounts:
-  auto_register: false
-  email_assignment_strategy: 0
-  email_hostname: ''
-  email_attribute: ''
-  auto_assigned_roles: {  }
-  restrict_password_management: true
-  restrict_email_management: true
-advanced:
-  debug_log: false
-  connection_timeout: 10
-login_link_enabled: true
-login_link_label: 'Log in via single sign-on (CAS)'

config/install/cas_attributes.settings.yml

-fetch:
-  frequency: 0
-  overwrite: 0
-field:
-  field_mapping: ''
-role:
-  role_mapping: ''
-  deny_no_match: 0
-  deny_registration_no_match: 0

config/install/responsive_menu_combined.settings.yml

-menus:
-  main: 'This Site'
-  uw-menu-global-header: UWaterloo
-display_parent_title: 0
-html_tags: h2