[Bug][Go]: Metrics incremented in Setup methods are not recalled.

### What happened?

Because the ParDo [Setup context is uncached](https://github.com/apache/beam/blob/833261f0a041e04ca4dcb8719424fda09edcc5e6/sdks/go/pkg/beam/core/runtime/exec/pardo.go#L104) metrics initialized in Setup are lost, which is unexpected. Work done in setup, while logically outside of a bundle, will be under the context of the first bundle to execute that transform.

So there needs to be a way to transfer/extract the metrics from the Setup context so they are recorded back to the runner.

### Issue Priority

Priority: 3 (minor)

### Issue Components

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