The ornamental design for a heatingvest, as shown and described.
FIG. 1 is a front view of a heating vest showing my new design;
FIG. 2 is another front view thereof;
FIG. 3 is a back view thereof;
FIG. 4 is a right side view thereof; and,
FIG. 5 is a left side view thereof.
The broken line showing of the heating elements as raised portions of the body of the vest is for the purpose of depicting portions of the article that form no part of the claimed design.