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This makes it clear that `mock_redis` has no runtime dependencies.

Change-Id: I814b67f1252285fe16455d9954f46edba3272dde
Reviewed-on: http://gerrit.causes.com/37011
Reviewed-by: Shane da Silva <6f6e68d1df92f30cb4b3ce35260ddf94a402f33d@causes.com>
Tested-by: Shane da Silva <6f6e68d1df92f30cb4b3ce35260ddf94a402f33d@causes.com>

anujdas/mock_redis,GearboxSoftware/mock_redis,tsubery/mock_redis,brigade/mock_redis,batizhevsky/mock_redis