The ornamental design for a cuttinginsert, as shown and described.
FIG. 1 is an isometric view of a cutting insert showing our new design;
FIG. 2 is side view of the cutting insert of FIG. 1, each side view being identical to each other; and,
FIG. 3 is a top view of the cutting insert of FIG. 1, the bottom view being identical to the top view.
The broken lines of FIGS. 1 and 2 are included for the purpose of illustrating structural portions of the cutting insert and form no part of the claimed design.