An ammunition supplier testified at the “Rust” shooting trial Monday that he only provided inert dummy rounds to the Western movie where actor Alec Baldwin fatally shot a cinematographer in 2021, though he also was handling live rounds from another production at that time.Albuquerque-based movie firearms and ammunition supplier Seth Kenney took the stand at the trial of “Rust” movie armorer Hannah Gutierrez-Reed, who is charged with involuntary manslaughter and evidence tampering in the death of cinematographer Halyna Hutchins.Kenney told a jury he cleaned and repackaged ammunition to…