Fix /consumers authority caching

[tnorling]

Last year we made a change to ensure /organizations and /common authority are cached with the tenantId and don't result in cache misses when the tenantId is not explicitly provided. We missed the /consumers authority which is now potentially leaving the cache in a state that contains both /consumers and a tenanted authority for the same set of scopes and throws a multiple authority error.

Also removes multiple authority error which is no longer doing what it was originally intended to do (throw when multiple cache entries existed for the same scope but different authorities). If a cache entry is not found for the provided scopes and authority it should result in a cache miss regardless of what other tokens are available in the cache.

[coveralls]

Coverage remained the same at 83.413% when pulling 66eafec on fix-token-caching-for-consumers-authority into 0b34c58 on dev.

[sameerag]

Lgtm. Approving this for now. I remember there is an MSA passthru use case that needs to be tested here, I will reach out with details. We can unblock this PR but lets follow through.