The ornamental design for a petgarment, as shown and described.
FIG. 1 is a bottom perspective view of a pet garment showing our new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left-side elevational view thereof;
FIG. 5 is a right-side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The shorter, thinner, evenly spaced broken lines on the pet garment depict stitching which forms no part of the claimed design. The longer, thicker, evenly spaced broken lines depict portions of the pet garment that form no part of the claimed design.