The ornamental design for a shoe upper, as shown and described.
FIG. 1 is a first side view of a shoe showing my design;
FIG. 2 is a side perspective view thereof; and,
FIG. 3 is a top view thereof.
The long-and-short broken lines form an unclaimed boundary around at least a portion of the claimed subject matter, and form no part of the claim. The even-length broken lines, which show the remainder of the article, are directed to environment, represent unclaimed subject matter, and form no part of the claimed design.