Use newBlockFilter signal from status-go

[yenda]

Problem

Currently transactions confirmations is updated as part of the transaction fetching loop so it is delayed and based on information provided by a third party

Rationale

While trivial, this issue will be done first as part of wallet improvement because it is the simplest use case for the newly added status-go subscriptions to eth filters

Implementation

• Use status-go eth_newBlockFilter signal to update current block number
• base number of confirmations in transaction details on the current block number

Acceptance Criteria

• number of confirmations in transaction details is updated within 2 seconds of a new block mined on chain