This fixes a number of CVEs and bugs:

* https://www.ruby-lang.org/en/news/2024/04/23/ruby-3-1-5-released/
* https://www.ruby-lang.org/en/news/2024/04/23/ruby-3-2-4-released/

This drops the `fix-ruby-xfree-for-libxml2` patch for Ruby 3.1.5 since
the change has been merged upstream.

This will also enable us to update to Puma 6.4.2 since
https://bugs.ruby-lang.org/issues/19837 has been resolved in Ruby
3.1.5.

Due to https://bugs.ruby-lang.org/issues/20451, Ruby 3.1.5 does not
compile on systems with libffi < 3.2 (such as UBI-8). This patch pulls
in https://github.com/ruby/ruby/pull/10696.

Changelog: changed