Make readTotalProduction fail fast on encountering a parse failure.

In response to review feedback:

#2111 (comment)

lib/core/src/Cardano/Pool/DB/Sqlite.hs

@@ -212,8 +212,12 @@ newDBLayer trace fp timeInterpreter = do
  pure (foldl' toMap Map.empty production)
 
  readTotalProduction =
- Map.fromList . rights . fmap parseRow <$> rawSql query []
+ Map.fromList . fmap (assertSuccess . parseRow) <$> rawSql query []
  where
+ assertSuccess = flip either id $ \e -> error $ mconcat
+ [ "readTotalProduction: unexpected parse failure: "
+ , show e
+ ]
  query = T.unwords
  [ "SELECT pool_id, count(pool_id) as block_count"
  , "FROM pool_production"