Airflow 2.1.0, Docker

**What happened**:

Users with the Guest role assigned are stuck in a redirect loop once they attempt to login successfully to the web interface.

**What you expected to happen**:

Get minimal access to the dashboard with the appropriate views for a guest role

**How to reproduce it**:
1. Assign a guest role to any user and remove any other roles with the administrator user.
2. Logout from the admin account 
3. Login as the guest user
4. You will notice constant HTTP redirects, and the dashboard will not show up.


tests/www/test_security.py
role_name = 'Test_Role'
        role_perms = []
        mock_roles = [{'role': role_name, 'perms': role_perms}]
        self.security_manager.bulk_sync_roles(mock_roles)
        role = self.security_manager.find_role(role_name)
        perm = self.security_manager.get_permission(permissions.ACTION_CAN_EDIT, permissions.RESOURCE_ROLE)
        self.security_manager.add_permission_role(role, perm)
        role_perms_len = len(role.permissions)
        self.security_manager.bulk_sync_roles(mock_roles)
        new_role_perms_len = len(role.permissions)
        assert role_perms_len == new_role_perms_len
        assert new_role_perms_len == 1
    def test_verify_public_role_has_no_permissions(self):
        public = self.appbuilder.sm.find_role("Public")
        assert public.permissions == []
    def test_verify_default_anon_user_has_no_accessible_dag_ids(self):
        with self.app.app_context():
            user = mock.MagicMock()
            user.is_anonymous = True
            self.app.config['AUTH_ROLE_PUBLIC'] = 'Public'
            assert self.app.appbuilder.sm.get_user_roles(user) == [self.app.appbuilder.sm.get_public_role()]
            self._create_dag("test_dag_id")
            self.security_manager.sync_roles()
            assert self.security_manager.get_accessible_dag_ids(user) == set()
    def test_verify_default_anon_user_has_no_access_to_specific_dag(self):