[UPDATE] fix wrong attribute name

The class Border has a rectList member, but some lines in
drawRects() refered to a member attribute named list. This caused the
test to fail again on PySide6, test passes now with these modifications.

Author: martinschwinzerl

qwt/plot_canvas.py

@@ -74,9 +74,9 @@ def drawRects(self, rects, count):
         if QT_API.startswith("pyside"):
             # Pyside
             if isinstance(rects, (QRect, QRectF)):
-                self.border.list = [rects]
+                self.border.rectList = [rects]
             elif isinstance(rects, list):
-                self.border.list += rects
+                self.border.rectList += rects
             else:
                 for i in range(count):
                     self.border.rectList += [rects.getRect().index(i)]