The ornamental design for a wildfireextinguishingsystem, as shown.
FIG. 1 is a perspective view of a wildfire extinguishing system;
FIG. 2 is a first side view (second side view is mirror image of first side view) thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a back view thereof;
FIG. 5 is a top view thereof; and,
FIG. 6 is a bottom view thereof.
The broken lines shown on the top of the wildfire extinguishing system is included for the purpose of illustration and forms no part of the claimed design.