The ornamental design for a set of shirtsleeves, as shown and described.
FIG. 1 is a front view of a set of shirt sleeves, showing my new design;
FIG. 2 is a rear view thereof;
FIG. 3 is a left side elevation view thereof;
FIG. 4 is a right side elevation view thereof;
FIG. 5 is a right side elevation view of the left sleeve; and,
FIG. 6 is a left side elevation view of the right sleeve.
The broken lines shown in the drawings illustrate environmental subject matter only and form no part of the claimed design. The dashed-dot lines shown in FIGS. 1, 2, 5 and 6 illustrate a boundary and form no part of the claimed design.