feat: Switch back to native yaml decoding

[nieomylnieja]

Motivation

When recently working on Data Export, we've encountered a problem using json.RawMessage with go-yaml decoding.
The raw message was used to postpone decoding of Data Export spec until we could decide what type should it be decoded to.
Due to time limitations back then we went with the easier solution and decided to use yaml.YAMLToJSON, which converts YAML to JSON and then uses encoding/json to decode the spec.

This is not ideal.
Doing it this way we're adding a decoding overhead, that's one thing.
Another, more serious issue is that we're stripping ourselves from receiving detailed syntax errors for YAML.
Instead, we're always getting JSON errors.

By adding serdeutil package and RawMessage which implements both JSON and YAML (un)marshalers we're bringing the aforementioned capabilities back home.

Release Notes

Syntax errors when parsing YAML now return more specific details.

[nieomylnieja]

As a side note, I can't really recall why this was a problem in first place:

		// Workaround for https://github.com/goccy/go-yaml/issues/313.
		// If the library changes its interpretation of empty pointer fields,
		// we should switch to native yaml.Unmarshal instead.

All the unit tests are passing, and revisiting the mentioned issue actually makes me wonder If it is in fact an issue 🤷

[daniel-zelazny]

Clever solution 🚀