I claim the ornamental design for a storage container for breast milk bags, as shown and described.
FIG. 1 is a top, front, right side perspective view showing the new design of a storage container for breast milk bags;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a right side elevational view thereof;
FIG. 5 is a top plan view thereof; and,
FIG. 6 is a bottom plan view thereof.
The short dash, short dash broken lines immediately adjacent to the shaded areas shown in FIGS. 1-4 represent the boundary of the claimed design. The long dash, short dash, short dash broken lines and boundary within shown in FIG. 2 represent portions of the storage container for breast milk bags that form no part of the claimed design. None of the broken lines form part of the claimed design.