[cgi] Cookie prefix spoofing in CGI

CGI::Cookie.parse in Ruby through 2.6.8 mishandles security prefixes in cookie names. This also affects the CGI gem prior to versions 0.3.1, 0.2.1, 0.1.1, and 0.1.0.1 for Ruby.
References

https://nvd.nist.gov/vuln/detail/CVE-2021-41819
https://hackero…