The ornamental design for a dishrack, as shown and described.
FIG. 1 is a perspective view of a new, original and ornamental design for a dish rack, support arms of the dish rack in a first position relative to a base;
FIG. 2 is a front elevation view of FIG. 1;
FIG. 3 is a rear elevation view of FIG. 1;
FIG. 4 is a right side elevation view of FIG. 1;
FIG. 5 is a left side elevation view of FIG. 1;
FIG. 6 is a top plan view of FIG. 1;
FIG. 7 is a bottom plan view of FIG. 1; and,
FIG. 8 is another perspective view of the dish rack, support arms of the dish rack in a second position relative to the base.
The broken lines in the drawings depict portions of the dish rack that form no part of the claimed design.