The ornamental design for a sensor, as shown and described.
FIG. 1 is a front view of a sensor showing our new design;
FIG. 2 is a left-front perspective view of the sensor;
FIG. 3 is a right-front perspective view of the sensor;
FIG. 4 is a rear view of the sensor;
FIG. 5 is a left-rear perspective view of the sensor;
FIG. 6 is a top view of the sensor;
FIG. 7 is a right-side view of the sensor;
FIG. 8 is a bottom view of the sensor;
FIG. 9 is a left-side view of the sensor; and,
FIG. 10 is a front view of a sensor according to a second embodiment showing our new design, all other views of the second embodiment are identical to that of the first embodiment but have not shown for ease of illustration.
The broken lines are included for purposes of illustrating a portion of the sensor that forms no part of the claimed design.