The ornamental design for a handle assembly, as shown and described.
FIG. 1 is a perspective view of a handle assemble showing our new design.
FIG. 2 is a front elevational view thererof.
FIG. 3 is a top plan view thereof.
FIG. 4 is a bottom plan view thereof.
FIG. 5 is a first side view thereof; and,
FIG. 6 is a second side view thereof.
The broken lines are shown in the views for illustrative purposes only, for form no part of the claimed design. The back elevational view does not form part of the claimed design.