The library-go helper function IsCloudProviderExternal should be updated to use the upstream feature gate DisableCloudProviders. Additionally, we should ensure that the feature gate and cloud provider combinations will not fail in situations where the feature is set but we do not have a CCM for the cloud provider.

DoD

• update IsCloudProviderExternal to use DisableCloudProviders feature gate
• ensure tests are validating the condition where the feature gate is set but our provider does not have a CCM yet