The top `.editorconfig` rule `charset = utf-8` now applies to batch files
```
mruby % file -I mrbgems/mruby-bin-config/mruby-config.bat
mrbgems/mruby-bin-config/mruby-config.bat: text/x-msdos-batch; charset=us-ascii
```
US-ASCII (basic English) is a 7-bit, 128 characters code page, originally designed for telegraphy.
UTF-8 encoding uses the same encoding as 7-bit ASCII for its first 128 characters. So a text file that only contains characters from that range of the first 128 characters will be identical at a byte level whether encoded with UTF-8 or 7-bit ASCII.
https://stackoverflow.com/questions/11303405/force-encode-from-us-ascii-to-utf-8-iconv