The ornamental design for a shoe upper, as shown and described.
FIG. 1 is a lateral rear perspective view of a shoe upper showing my new design;
FIG. 2 is a rear view thereof;
FIG. 3 is a medial rear perspective view thereof; and,
FIG. 4 is a top rear perspective view thereof.
The broken lines immediately adjacent to the shaded area define the bounds of the claimed design, and form no part thereof. The unshaded race-track-shaped region within the shaded area forms no part of the claimed design. The broken lines showing the remainder of the shoe are for environmental purposes only, and form no part of the claimed design.