Major Description
In StoreChangelogReader#validatePartitionExists, if the metadata for the required partition is not available, or a timeout exception is thrown, today the function would directly throw the exception all the way up to user's exception handlers.
Since we have now extracted the restoration out of the consumer callback, a better way to handle this, is to only validate the partition during restoring, and if it does not exist we can just proceed and retry in the next loop
