The ornamental design for a cuvette, as shown and described.
FIG. 1 is a front, top, and left side perspective view of a cuvette according to the design;
FIG. 2 is a front view thereof;
FIG. 3 is a left side view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof;
FIG. 7 is a rear view thereof;
FIG. 8 is a cross-sectional view taken along line 8-8 of FIG. 2; and,
FIG. 9 is a cross-sectional view taken along line 9-9 of FIG. 4.
The dash lines depict portions of the cuvette that form no part of the claimed design. The dot dash broken lines depict the boundaries of the claim and form no part thereof.