The ornamental design for a connectingpin, as shown and described.
FIG. 1 is a perspective view of a connector pin showing my new design;
FIG. 2 is an elevational view thereof;
FIG. 3 is another elevational view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof; and,
FIG. 6 is a perspective view thereof, shown in the environmental use of a draw bar along with an attachment.
The broken lines adjacent to the surface shading define the boundary and form no part of the claimed design. Other broken lines illustrate unclaimed portions and environment of the claimed design. None of the broken lines form part of the claimed design.