Fee rate history is not updated timely

[Keith-CY]

I've pushed numerous transactions with fee_rate 2,816 shannons/kB

Almost all transactions in blocks are mine.

But there are always hundreds of transactions with fee_rate 1,000 shannons/kB in the recent 10,000 transactions

[zmcNotafraid]

Current calculate query condition is: CkbTransaction.tx_committed.where("bytes > 0 and transaction_fee > 0 and confirmation_time > 0").
When I query above txs from database, these confirmation_time is nil, so they can't calcuate.
Only fetch by websocket pending txs have set confirmation time.

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[zmcNotafraid]

related issue: #704