Reduce logging in the datastore check and gc process

For the DataStore check consistency and GC process there's quite a bit of INFO logging

• For size of the each blob (Should be debug)
• Downloading of blob ids from the blob store currently logs every 1000 blobs which should be changed to 100000 or so to not flood the logs but also indicate progress
• Collecting blob references logs for each in memory blob which can be ignored