Method gen-strings exceeds limit for UTF-8

[lzap]

Hello,

generation of UTF-8 strings (CJK, UTF8) does not respect byte limit (255 in my example) and can return string longer than given bytes:

RFauxFactory.gen_strings(1..255).values
RFauxFactory.gen_utf8(1..255)
RFauxFactory.gen_cjk(1..255)

Expected behaviour is obviously to respect the limit. In Foreman codebase, I've temporarily used truncate_bytes method from Rails 6+ to fix that.

RFauxFactory.gen_strings(1..255).values.map {|x| x.truncate_bytes(255, omission: '')},