Add go cache in the global setup script

[blues-man]

This will prepare the go modules avoiding wasting time on CDN throttling

[blues-man]

@yuriolisa @madorn this is now pushed in Prod for:

• Operator SDK with Go, Memcached | Track
• Operator SDK with Helm, Memcached | Track

Can you confirm that all work in prod with this operator-sdk init command in the setup script to have already the go cache ready?