The ornamental design for a roof vent assembly, as shown and described.
FIG. 1 is a Perspective View of the roof vent assembly;
FIG. 2 is a Front Elevational View of the roof vent assembly;
FIG. 3 is a Side Elevational View of the roof vent assembly; and,
FIG. 4 is a Top Plan View of the roof vent assembly.
The claimed design is shown with a symbolic break in its length. The appearance of any portion of the article between the break lines forms no part of the claimed design.
The broken lines illustrate portions of the roof vent assembly that form no part of the claimed design.