The ornamental design for a packagingcontainer, as shown and described.
FIG. 1 is a perspective view of a packaging container.
FIG. 2 is a front view of the packaging container of FIG. 1.
FIG. 3 is a top view of the packaging container of FIG. 1; and,
FIG. 4 is a bottom view of the packaging container of FIG. 1.
Rear, left side, and right side views are omitted as they each are same as the front view.
The broken lines in the drawings showing the packaging container illustrate the portions of the packaging container that form no part of the claimed design.