.editorconfig: do not specify line ending

That is annoying on Windows, since the editor will change the file if
you just open it. Git will checking as LF anyway.

.editorconfig

@@ -4,7 +4,6 @@ root = true
 
 [*]
 charset = utf-8
-end_of_line = lf
 insert_final_newline = true
 trim_trailing_whitespace = true