The ornamental design for a connector, as shown and described.
FIG. 1 is a front top perspective view of a connector showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a top view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof; and,
FIG. 7 is bottom view thereof.
The broken lines immediately adjacent to the shaded areas define the bounds of the claimed design and form no part thereof. The broken lines depicting the remainder of the connector show features that form no part of the claimed design.