The ornamental design for a candy, as shown and described.
FIG. 1 is a front side view of the candy, which is the same as the back side view.
FIG. 2 is a right side view of the candy, which is the same as the left side view.
FIG. 3 is a perspective view from above and one side of the candy.
FIG. 4 is a top view of the candy; and,
FIG. 5 is a bottom view of the candy.
The broken lines shown in FIGS. 1-3 and 5 are for illustrative purposes, i.e., when the candy is presented as a lollipop with a stick, and form no part of the claimed design.