hotfix - handle errors fetching recipe

etching recipe: 649195

[2025-06-17 11:22:20,821: WARNING/MainProcess] Captured recipe details for Lamb Burgers With Tzatziki Sauce

[2025-06-17 11:22:20,870: WARNING/MainProcess] Error fetching recipe: {'unit': ['This field cannot be blank.']}

[2025-06-17 11:22:20,877: INFO/MainProcess] Task apps.recipes.tasks.fetch_recipe_details[a5ec166f-5343-4412-85a4-b10f0954c496] succeeded in 1.734692021011142s: {'success': False, 'recipe_id': '649195', 'error': '{\'unit\': [\'This field cannot be blank.\']}'}