The ornamental design for a fabric, as shown and described.
FIG. 1 is a front view of a fabric showing our new design;
FIG. 2 is perspective view thereof; and,
FIG. 3 is an enlarged detail view of the area circumscribed by the two arrowed lines labeled 3 within FIG. 1.
The broken lines surrounding FIGS. 1 and 2 depict the boundaries of the claim and form no part thereof. The broken line around FIG. 3 illustrates the boundary of the detail area and forms no part of the claimed design.