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 broken lines immediately adjacent to the shaded area represent unclaimed boundaries of the design. The two unshaded regions within the shaded area that are demarcated by broken lines form no part of the claimed design. The contrast in shading represents a contrast in appearance only and does not represent any particular color, material, texture or finish. The broken lines showing the remainder of the shoe represent unclaimed subject matter and form no part of the claimed design.