The ornamental design for a grill, as shown and described.
FIG. 1 is a front, top perspective view of a grill showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a top view thereof; and,
FIG. 7 is a bottom view thereof.
The features shown in broken lines depict portions of the grill and associated components that form no part of the claimed design. The bolded long dash-short dash lines indicate the bounds of the claim and otherwise form no part of the claimed design.