Evaluation of Gut-Related Well-Being and Mood Effects of a Daily Nutritional Food Ingredient From the Co-Fermentation of Fungal Mycelium (Pleurotus Pulmonarius) and Microalgae (Chlorella Vulgaris) in Healthy Adults Experiencing Minor Gastrointestinal Discomfort: A 30-Day, Two-Arm, Open-Label Study | Arctuva