chore(style): remove the trailing space from all source files (#3188)

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>

examples/widgets/dropdown/lv_example_dropdown_1.py

@@ -1,7 +1,7 @@
 def event_handler(e):
     code = e.get_code()
     obj = e.get_target()
-    if code == lv.EVENT.VALUE_CHANGED: 
+    if code == lv.EVENT.VALUE_CHANGED:
         option = " "*10 # should be large enough to store the option
         obj.get_selected_str(option, len(option))
         # .strip() removes trailing spaces

examples/widgets/dropdown/lv_example_dropdown_3.py

@@ -12,10 +12,10 @@ try:
 except:
     print("Could not find img_caret_down.png")
     sys.exit()
-    
+
 img_caret_down_argb = lv.img_dsc_t({
   'data_size': len(png_data),
-  'data': png_data 
+  'data': png_data
 })
 
 def event_cb(e):