The ornamental design for a container, as shown and described.
FIG. 1 is a top front perspective view of a container showing our new design;
FIG. 2 is a bottom rear perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a rear view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a top view thereof;
FIG. 8 is a bottom view thereof;
FIG. 9 is a top front perspective view of the container with environmental subject matter inserted to show the design in a position of use;
FIG. 10 is a second top front perspective view of the container with environmental subject matter included to show the design in a position of use; and,
FIG. 11 is a third top front perspective view of the container with environmental subject matter included to show the design in a position of use.
The dot-dash lines in the FIGURES and the areas within the dot-dash lines show environment that forms no part of the claimed design.