Store total gas_used in addresses table

[vbaranov]

Motivation

Query to get total gas_used on address is quite long and for a huge number of transactions is executing more than 60secs resulting in 0 gas_used in UI because the calculation is synchronous.

Changelog

Together with updating of gas_used on address cache, update the value in the DB. For this aim, the gas_used column is added to the addresses table. And use the value from the table as a fallback if the cache was not updated in time.

Checklist for your Pull Request (PR)

• I added an entry to CHANGELOG.md with this PR
• If I added new functionality, I added tests covering it.
• If I fixed a bug, I added a regression test to prevent the bug from silently reappearing again.
• I checked whether I should update the docs and did so by submitting a PR to https://github.com/blockscout/docs
• If I added/changed/removed ENV var, I submitted a PR to https://github.com/blockscout/docs to update the list of env vars at https://github.com/blockscout/docs/blob/master/for-developers/information-and-settings/env-variables.md and I updated the version to master in the Version column. Changes will be reflected in this table: https://docs.blockscout.com/for-developers/information-and-settings/env-variables.
• If I add new indices into DB, I checked, that they are not redundant with PGHero or other tools