Revisit failing CRA check around COS network access restriction

[ocofaigh]

Currently we are ignoring the rule Check whether Cloud Object Storage network access is restricted to a specific IP range in the CRA ignore rule file. We need to finalise what to do here, since network access restriction should be done by CBRs. However should the Da actually support creating the CBRs, or is the idea that the CBRs would be in place by the time the DA ran?

[ocofaigh]

#101