Go Coordinator should do a "Returning" instead of re-getting

[Ishiihara]

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The go coordinator is using a in memory cache to keep consistent with the system catalog, as a result, the system catalog APIs such as CreateCollection, UpdateCollection will call GetCollections to return the necessary information from the catalog. This may cause additional load to the database and is not necessary. We may be able to reduce the call to the database by using returning.