The ornamental design for a cap for a deodorant or antiperspirant container, as shown.
FIG. 1 is a perspective view of a cap for a deodorant or antiperspirant container embodying our new design, shown on a deodorant or antiperspirant container;
FIG. 2 is a front side view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a rear side view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken line showing of deodorant or antiperspirant container depicts environment only and forms no part of the claimed design.