Add option to Go process metrics to fallback to pre v1.12.0 behaviour.

[bwplotka]

AC:

• As per comment, there is a variadic option on func NewGoCollector() prometheus.Collector, so func NewGoCollector(opts...GoOption) prometheus.Collector where GoOption is some func(o *goOptions) and then we can have WithMemStatsEnabled(bool) WithRuntimeMetricsEnabled(bool) and both true by default, which allows to customize metric behaviour.

cc @kakkoyun @mknyszek