GHSA-wc64-c5rv-32pf

### Impact The in-toto configuration is read from various directories and allows users to configure the behavior of the framework. The files are from directories following the XDG base directory specification [1]. Among the files read is `.in_totorc` which is a hidden file in the directory in which in-toto is run. If an attacker controls the inputs to a supply chain step, they can mask their activities by also passing in an `.in_totorc` file that includes the necessary exclude patterns and settings. RC files are widely used in other systems [2] and security issues have been discovered in their implementations as well [3]. We found in our conversations with in-toto adopters that `in_totorc` is not their preferred way to configure in-toto. As none of the options supported in `in_totorc` is unique, and can be set elsewhere using API parameters or CLI arguments, we decided to drop support for `in_totorc`. ### Other Recommendations Sandbox functionary code as recommended in https://github.com/in-toto/docs/security/advisories/GHSA-p86f-xmg6-9q4x. ### References [1] https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html [2] https://spec.editorconfig.org/ [3] https://github.blog/2022-04-12-git-security-vulnerability-announced/