Migrating from go-kit/kit/log to the slimmer go-kit/log.

[cristiangreco]

For consistency with Cortex and Prometheus, see

• Migrating from go-kit/kit/log to the slimmer go-kit/log cortexproject/cortex#4421
• Migrate From go-kit/kit/log to go-kit/log prometheus/prometheus#8927

[bboreham]

Please can you pin github.com/go-kit/kit to v0.12.0 to avoid inconsistencies between it and github.com/go-kit/log.
See cortexproject/cortex#4544

[cristiangreco]

@bboreham have updated the go.mod file and run a go mod tidy, which brings in other updates.

[CLAassistant]

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[colega]

Hey, @cristiangreco, are you going to work on this or we can close it as stale?

[cristiangreco]

Closing this, happy for someone else to push this change forward, if needed.