chore(ruby): pin 'psych' gem to 4.0.6

[jonas-jonas]

Related Issue or Design Document

Checklist

• [ ] I have read the contributing guidelines and signed the CLA.
• [ ] I have referenced an issue containing the design document if my change introduces a new feature.
• [ ] I have read the security policy.
• [ ] I confirm that this pull request does not address a security vulnerability. If this pull request addresses a security vulnerability, I confirm that I got approval (please contact security@ory.sh) from the maintainers to push the changes.
• [ ] I have added tests that prove my fix is effective or that my feature works.
• [ ] I have added the necessary documentation within the code base (if appropriate).

Further comments

[jonas-jonas]

@aeneasr pretty ugly fix, but I think the generator needs to be updated here. Not sure what we can do, except this...

It pins the version of psych to 4.0.6 in the ruby client: