The ornamental design for a handle assembly, as shown and described.
FIG. 1 is a top front perspective view of a handle assembly showing my new design;
FIG. 2 is a reduced exploded top front perspective view of the handle of FIG. 1;
FIG. 3 is a front view of the handle of FIG. 1;
FIG. 4 is a side view of the handle of FIG. 1;
FIG. 5 is a bottom view of the handle of FIG. 1; and,
FIG. 6 is a top view of the handle of FIG. 1.
The broken line showing of the middle section and bottom protrusions in FIG. 2 is included for the purpose of illustrating portions of the handle and forms no part of the claimed design.