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.


airflow/www/views.py
"""Returns appropriate permission name depending on request method name."""
        if request:
            action_name = request.view_args.get("name")
            _, method_name = request.url_rule.endpoint.rsplit(".", 1)
            if method_name == 'action' and action_name:
                return self.class_permission_name_mapping.get(action_name, self._class_permission_name)
            if method_name:
                return self.class_permission_name_mapping.get(method_name, self._class_permission_name)
        return self._class_permission_name
    @class_permission_name.setter
    def class_permission_name(self, name):
        self._class_permission_name = name
class CustomUserLDAPModelView(MultiResourceUserMixin, UserLDAPModelView):
    """Customize permission names for FAB's builtin UserLDAPModelView."""
    pass
class CustomUserOAuthModelView(MultiResourceUserMixin, UserOAuthModelView):
    """Customize permission names for FAB's builtin UserOAuthModelView."""
    pass
class CustomUserOIDModelView(MultiResourceUserMixin, UserOIDModelView):
    """Customize permission names for FAB's builtin UserOIDModelView."""
    pass
class CustomUserRemoteUserModelView(MultiResourceUserMixin, UserRemoteUserModelView):
    """Customize permission names for FAB's builtin UserRemoteUserModelView."""
    pass