Upgrade gopkg.in/yaml.v2 to gopkg.in/yaml.v3

[inteon]

replacement PR of #1204

[github-actions]

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[sagikazarmark]

@inteon Thanks for rebasing!

I asked the author of go-yaml about plans to release a new version. I'm not that familiar with it, but I'm a bit reluctant pulling in an untagged version.

Let's see what they say.

[sagikazarmark]

@inteon thanks for this PR! I decided to hide yaml v3 behind a build tag until there is more information available about an official release.