Remove file UTF BOM.
The UTF-8 BOM is a sequence of bytes (EF BB BF) that allows the reader to identify a file as being encoded in UTF-8.
Normally, the BOM is used to signal the endianness of an encoding, but since endianness is irrelevant to UTF-8, the BOM is unnecessary.
According to the Unicode standard, the BOM for UTF-8 files is not recommended
composer install
php ./fixer fix dir_name_or_file_name [--extension=php]