The ornamental design for a shoe upper, as shown and described.
FIG. 1 is a side view of a shoe upper showing my new design;
FIG. 2 is a front perspective view thereof; and,
FIG. 3 is a rear perspective 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.