Currently ShardingCatalogTestFixture sets up both a ShardingCatalogClientImpl and a ShardingCatalogManagerImpl. The config shard, however, is still a ShardRemote. That means that any tests using ShardingCatalogManagerImpl will be acting as though the ShardingCatalogManagerImpl were talking to a remote config server, which is never what will happen in non-test code.

We also have ConfigServerTestFixture, which also sets up both a ShardingCatalogClientImpl and a ShardingCatalogManagerImpl, but with the config server as a LocalShard. This is closer to how things work in prod code. Thus all tests that use ShardingCatalogManagerImpl should be converted to use ConfigServerTestFixture instead of ShardingCatalogTestFixture.

We should also probably then rename ShardingCatalogTestFixture to ShardingCatalogClientTestFixture.