The ornamental design for a jacket, as shown and described.
FIG. 1 is a front right perspective view of a jacket showing my new design in an in-use state;
FIG. 2 is a right side view thereof;
FIG. 3 is a left side view thereof;
FIG. 4 is a front view thereof;
FIG. 5 is an enlarged partial view of the claimed design of FIG. 1 with environment removed for clarity purposes;
FIG. 6 is an enlarged partial view of the claimed design of FIG. 2 with environment removed for clarity purposes;
FIG. 7 is an enlarged partial view of the claimed design of FIG. 3 with environment removed for clarity purposes; and,
FIG. 8 is an enlarged partial view of the claimed design of FIG. 4 with environment removed for clarity purposes.
The broken lines immediately adjacent to the shaded area define the bounds of the claimed design and form no part thereof. The broken lines depicting the remainder of the jacket show features that form no part of the claimed design.