[test-strategy]Add infra-operator specific rules

[gibizer]

This is based on the comment from @stuggi in https://github.com/openstack-k8s-operators/docs/pull/20

[dprince]

Not blocking. Just a slight preference that the service operator specific rules be in the respective repositories (lib-common, infra-operator, nova, etc.). I wouldn't look for them in the docs repo myself

[gibizer]

Not blocking. Just a slight preference that the service operator specific rules be in the respective repositories (lib-common, infra-operator, nova, etc.). I wouldn't look for them in the docs repo myself

Eventually I would like this to move there. But for now I would like to have a central place listing our testing rule to:

• to use a dashboard showing where we are with implementing the strategy
• to serve as a sure of peer pressure for other operators to adopt the startegy