The ornamental design for a shoe upper, as shown and described.
FIG. 1 is a front perspective view of a shoe upper showing my new design;
FIG. 2 is a side view thereof; and,
FIG. 3 is a rear perspective view thereof.
The photographic area is claimed. The broken lines immediately adjacent to the photographic area represent unclaimed boundaries of the design. The lack of a broken or solid line immediately adjacent to the photographic area indicates a claimed edge of the design. The broken lines showing the remainder of the shoe are for environmental purposes only and form no part of the claimed design.