The ornamental design for a "cover lens for an automotive lamp", as shown and described.
FIG. 1 is a perspective view of a cover lens for an automotive lamp which embodies my new and original design therefor, the dashed line in FIG. 1 representing structural environment only therefor and forms no part of my claimed design;
FIG. 2 is a top plan view of thereof;
FIG. 3 is a bottom plan view thereof;
FIGS. 4 and 5 are right and left side elevational views thereof, respectively; and,
FIGS. 6 and 7 are front and rear side elevational views thereof, respectively.