The ornamental design for an outsole for a shoe, as shown and described.
FIG. 1 is a bottom perspective view of an outsole for a shoe in accordance with my new design;
FIG. 2 is a bottom view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a front view thereof;
FIG. 6 is a rear view thereof; and,
FIG. 7 is an enlarged view of the area labeled “7” in FIG. 1.
The broken lines shown in all of the figures are for environmental purposes and form no part of the claim. The shoe upper shown in broken lines in FIGS. 1, 3, 4, 5, and 6 is for environmental purposes only and forms no part of the claimed design.