otelmemcache deprecation

[pellared]

I am creating this issue to inform you that we (OpenTelemetry contributors) are planning to deprecate https://pkg.go.dev/go.opentelemetry.io/contrib/instrumentation/github.com/bradfitz/gomemcache/memcache/otelmemcache.

You can consider copying the OpenTelemetry instrumentation to this repository or organization. You can even consider instrumenting with OpenTelemetry "natively" (without requiring the users to use an instrumentation library). You can also check for more information here.