The ornamental design for a cleaningbrush, as shown.
FIG. 1 is a perspective view of a cleaning brush showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The portions of the cleaning brush shown broken lines form no part of the claimed design. The bristles are partially shown in FIGS. 2 and 3 for ease of illustration.