Air Purifier Market Size and Forecasts (2020 - 2030), Global and Regional Share, Trends, and Growth Opportunity Analysis Report Coverage: by Technique [High-Efficiency Particulate Air (HEPA), Ultraviolet Germicidal Irradiation (UVGI), Activated Carbon Filtration, Ionizer Purifiers, Others], End-User (Commercial, Residential, and Industrial), and Geography (North America, Europe, Asia Pacific, and South and Central America)