Sensor

FIG. 1 is a perspective view for a sensor according to our new ornamental design.

FIG. 2 is a rear view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines of the sensor represent environmental structure or features and do not form a part of the claimed design.