delete dir_path in wch bsp ignore_format file.

bsp/wch/arm/.ignore_format.yml

@@ -2,7 +2,5 @@
 # If you need to exclude an entire folder, add the folder path in dir_path;
 # If you need to exclude a file, add the path to the file in file_path.
 
-file_path:
-
 dir_path:
 - Libraries/CH32F10x_StdPeriph_Driver