Short description

1. Update rust version to 1.81.0
2. Start using serde_yml as a replacement for serde_yaml (a few tests needed update as the quoting rules on output changed).
3. Update Cargo.lock

I seems serde_yml (the fork) is actively maintained. A large part of the activity is adding unit test, so that feels good so far.

Checklist

I have:

• read the CONTRIBUTING.md document
• compiled this code
• tested this code
• included documentation (including possible behaviour changes)
• documented the code
• added or modified regression test(s)
• added or modified unit test(s)