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 top view thereof;
FIG. 3 is a side view thereof;
FIG. 4 is a second side view thereof;
FIG. 5 is a front view thereof; and,
FIG. 6 is an enlarged view of FIG. 2, shown in isolation from its environment.
The broken lines immediately adjacent to the photographic area define the bounds of the claimed design and form no part thereof. The broken lines showing the remainder of the shoe are for environmental purposes only and form no part of the claimed design.