Add that `CSV Injection` can be caused by a double-byte characters.

[k163377]

The CSV Injection can also be caused by a double-byte characters(＝, ＋, ー, ＠).
For example, ＝cmd|’ /C calc'!A0 is reproduced when executed in a Japanese environment.

This is not mentioned on this page, but I think it should be mentioned explicitly.
https://github.com/OWASP/www-community/blob/master/pages/attacks/CSV_Injection.md

However, I submitted this issue because I did not know what kind of verification was needed to add it, what words to choose, etc.
I apologize that I do not have Excel myself and can only help a little.