The ornamental design for a shoe upper, as shown and described.
FIG. 1 is a front photographic view of a shoe upper showing my new design;
FIG. 2 is a rear photographic view thereof;
FIG. 3 is a side photographic view thereof;
FIG. 4 is a second side photographic view thereof;
FIG. 5 is a top photographic view thereof; and,
FIG. 6 is a perspective photographic view thereof.
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 show represent unclaimed subject matter and form no part of the claimed design.