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/views/test_views_base.py
scheduler_status, last_scheduler_heartbeat = request.getfixturevalue(heartbeat)
    resp = admin_client.get('health', follow_redirects=True)
    resp_json = json.loads(resp.data.decode('utf-8'))
    assert 'healthy' == resp_json['metadatabase']['status']
    assert scheduler_status == resp_json['scheduler']['status']
    assert last_scheduler_heartbeat == resp_json['scheduler']['latest_scheduler_heartbeat']
def test_users_list(admin_client):
    resp = admin_client.get('users/list', follow_redirects=True)
    check_content_in_response('List Users', resp)
@pytest.mark.parametrize(
    "path, body_content",
    [("roles/list", "List Roles"), ("roles/show/1", "Show Role")],
)
def test_roles_read(admin_client, path, body_content):
    resp = admin_client.get(path, follow_redirects=True)
    check_content_in_response(body_content, resp)
def test_roles_read_unauthorized(viewer_client):
    resp = viewer_client.get("roles/list", follow_redirects=True)
    check_content_in_response('Access is Denied', resp)
@pytest.fixture(scope="module")
def delete_role_if_exists(app):
    def func(role_name):
        if app.appbuilder.sm.find_role(role_name):
            app.appbuilder.sm.delete_role(role_name)
    return func
@pytest.fixture()
def non_exist_role_name(delete_role_if_exists):