2021.4 secret changes breaks lovelace gen

[Petro31]

This pr changed how secrets work: home-assistant/core#47034. It causes lovelace_gen to break.

Traceback (most recent call last):
  File "/usr/src/homeassistant/homeassistant/components/websocket_api/decorators.py", line 18, in _handle_async_response
    await func(hass, connection, msg)
  File "/usr/src/homeassistant/homeassistant/components/lovelace/websocket.py", line 30, in send_with_error_handling
    result = await func(hass, connection, msg, config)
  File "/usr/src/homeassistant/homeassistant/components/lovelace/websocket.py", line 72, in websocket_lovelace_config
    return await config.async_load(msg["force"])
  File "/usr/src/homeassistant/homeassistant/components/lovelace/dashboard.py", line 188, in async_load
    is_updated, config = await self.hass.async_add_executor_job(
  File "/usr/local/lib/python3.8/concurrent/futures/thread.py", line 57, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/usr/src/homeassistant/homeassistant/components/lovelace/dashboard.py", line 207, in _load_config
    config = load_yaml(self.path, Secrets(Path(self.hass.config.config_dir)))
  File "/usr/src/homeassistant/homeassistant/util/yaml/loader.py", line 112, in load_yaml
    return parse_yaml(conf_file, secrets)
  File "/usr/src/homeassistant/homeassistant/util/yaml/loader.py", line 124, in parse_yaml
    yaml.load(content, Loader=lambda stream: SafeLineLoader(stream, secrets))
  File "/usr/local/lib/python3.8/site-packages/yaml/__init__.py", line 114, in load
    return loader.get_single_data()
  File "/usr/local/lib/python3.8/site-packages/yaml/constructor.py", line 51, in get_single_data
    return self.construct_document(node)
  File "/usr/local/lib/python3.8/site-packages/yaml/constructor.py", line 55, in construct_document
    data = self.construct_object(node)
  File "/usr/local/lib/python3.8/site-packages/yaml/constructor.py", line 100, in construct_object
    data = constructor(self, node)
  File "/usr/src/homeassistant/homeassistant/util/yaml/loader.py", line 254, in _ordered_dict
    nodes = loader.construct_pairs(node)
  File "/usr/local/lib/python3.8/site-packages/yaml/constructor.py", line 155, in construct_pairs
    value = self.construct_object(value_node, deep=deep)
  File "/usr/local/lib/python3.8/site-packages/yaml/constructor.py", line 100, in construct_object
    data = constructor(self, node)
  File "/usr/src/homeassistant/homeassistant/util/yaml/loader.py", line 173, in _include_yaml
    return _add_reference(load_yaml(fname, loader.secrets), loader, node)
  File "/config/custom_components/lovelace_gen/__init__.py", line 32, in load_yaml
    stream = io.StringIO(jinja.get_template(fname).render({**args, "_global": llgen_config}))
TypeError: 'Secrets' object is not a mapping