Contrast panel: fix "Set range" dialog title

Author: PierreRaybaut

plotpy/panels/contrastadjustment.py

@@ -586,7 +586,7 @@ def apply_callback(param: RangeParam) -> None:
             """Apply callback"""
             self.histogram.set_range(param.zmin, param.zmax)
 
-        param = RangeParam()
+        param = RangeParam(_("Set range"))
         zmin_0, zmax_0 = param.zmin, param.zmax = self.histogram.range.get_range()
         if param.edit(self, apply=apply_callback):
             apply_callback(param)