To what extent do different concentrations (100%, 75%, 50%, 25%) of Melaleuca alternifornila (tea tree), acetylsalicylic acid and a mixture of both in ratios 75:25, 50:50 and 25:75 (1:3, 1:1 and 3:1) inhibit the growth in area (in mm2) of Cutibacterium acnes cultured in vitro at 25°C for 5 days?