We claim the ornamental design for a vacuum cleaner, as shown and described.
FIG. 1 is a top, front and left side perspective view of a vacuum cleaner showing our new design;
FIG. 2 is a top, front and right side perspective view thereof;
FIG. 3 is a top, rear and right side perspective view thereof;
FIG. 4 is a top, rear and left side perspective view thereof;
FIG. 5 is a top and front perspective view thereof;
FIG. 6 is a top and right side perspective view thereof;
FIG. 7 is a top and rear perspective view thereof;
FIG. 8 is a top, front and right side perspective view with the handle in an alternate position; and,
FIG. 9 is a top and front perspective view with the handle in an alternate position.
The broken line showing of portions of the vacuum cleaner is for the purpose of illustrating portions of the vacuum cleaner and forms no part of the claimed design.