void removeExistingSnapshotSizes(List<Delete> deletes) throws IOException {
    try (Table quotaTable = conn.getTable(QuotaUtil.QUOTA_TABLE_NAME)) {
      quotaTable.delete(deletes);
    }
  }
Writes the size used by snapshots for each namespace to the quota table.
hbase-server/src/main/java/org/apache/hadoop/hbase/quotas/SnapshotQuotaObserverChore.java