fix dangling reference issue

kmk/extensions/rgb.py

@@ -275,11 +275,10 @@ class RGB(Extension):
         if 0 <= index <= self.num_pixels - 1:
             for pixels in self.pixels:
                 if index <= (len(pixels) - 1):
+                    pixels[index] = rgb
                     break
                 index -= len(pixels)
 
-            pixels[index] = rgb
-
             if not self.disable_auto_write:
                 pixels.show()