Switch from `gopkg.in/yaml.v{2|3}` to `go.yaml.in/yaml/v{2|3}`

[petersutter]

What would you like to be added:
see details in related issue on g/g gardener/gardener#12838

Why is this needed:

[gardener-ci-robot]

The Gardener project currently lacks enough active contributors to adequately respond to all issues.
This bot triages issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Mark this issue as fresh with /remove-lifecycle stale
• Mark this issue as rotten with /lifecycle rotten
• Close this issue with /close

/lifecycle stale

[gardener-ci-robot]

The Gardener project currently lacks enough active contributors to adequately respond to all issues.
This bot triages issues according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 60d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 60d of inactivity since lifecycle/rotten was applied, the issue is closed

You can:

• Mark this issue as active with /lifecycle active
• Mark this issue as frozen with /lifecycle frozen
• Mark this issue as fresh with /remove-lifecycle rotten
• Close this issue with /close

/lifecycle rotten