A Phase I, Randomized, Partial Double-blind, Single dose, 3-Way Cross-over Study to Assess the Lung Exposure Bioequivalence of Budesonide, Glycopyrronium, and Formoterol for BGF MDI HFO Compared with BGF MDI HFA Using an AeroChamber Plus Flow-Vu Spacer and to Compare the Lung Exposure of BGF MDI HFO with a Spacer to BGF MDI HFO without a Spacer