About page: content needs to be updated to OWASP Top 10 2021

Currently, the supported version of OWASP Top 10 is 2010. In general, we should update the WebGoat project to be compatible (contain vulnerabilities) of the newest standard.

I think we need to delay the update. Possibly a new OWASP version may be released before we will finalize the work. Also, first, we should include the vulnerabilities in the code.