Concurrent writes during block syncing check

[sync-by-unito[bot]]

The block syncing check contains two steps:

• Check if last block timestamp is not older than 30 seconds.
• Check if the last used block is less than the current one. Seconds step contains the problem: There is a place in skale-admin where last block written concurrently to the file. We can either disable second step completely. Or fix it

┆Issue is synchronized with this Jira Bug