Comply with RUSTSEC-2024-0320

[stanisloe]

Describe your changes

As discussed in linked issue yaml-rust is not maintened and poses a risk as future vulnerabilities or bugs in yaml-rust will not be addressed. Also it makes noise if you run cargo-audit. As advised in RUSTSEC-2024-0320 yaml-rust2 is a fully compliant YAML 1.2 implementation written in rust and works faster than its predecessor yaml-rust and fully compatible with it.
crates/app is the affected crate and it fetches yaml-rust from config crate.
I've udpated config crate to the latest version and fixed compilation errors and warnings.
The reason why I'm using commit version instead of release tag for config crate is that it's owner is looking for new maintainer and not releasing new tags until than. But yaml-rust2 issue was tested and merged to main branch from this pr so it should be safe to use.

Indicate on which release or other PRs this topic is based on

mehcode/config-rs#553
#2993

Checklist before merging to draft

• I have added a changelog
• Git history is in acceptable state

[tzemanovic]

rebased in #3305