Clean up goalzero (#40817)

* cleanup goalzero code

* more cleanup

* mroe cleanup

* log defined exception to error

* return None if not configured

* return False if not configured

tests/components/goalzero/test_config_flow.py

@@ -46,11 +46,6 @@ async def test_flow_user(hass):
             DOMAIN,
             context={"source": SOURCE_USER},
         )
-        assert result["type"] == RESULT_TYPE_FORM
-        assert result["step_id"] == "user"
-        assert result["errors"] == {}
-        _flow_next(hass, result["flow_id"])
-
         result = await hass.config_entries.flow.async_configure(
             result["flow_id"],
             user_input=CONF_CONFIG_FLOW,