The ornamental design for an aerial workplatform, as shown and described.
FIG. 1 is a front view of an aerial work platform according to my design;
FIG. 2 is a rear view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof;
FIG. 7 is a rear perspective view thereof;
FIG. 8 is a right side perspective view thereof; and,
FIG. 9 is a reference view thereof in an expanded position.
The broken lines shown in the figures are included for the purpose of illustrating portions of the aerial work platform that form no part of the claimed design.