Repair websocket subscription

[vbaranov]

Motivation

Websocket subscription to Ethereum node doesn't work

Changelog

Downgrade websocket_client dependency down to 1.3.0 (from 1.4.2)

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

[coveralls]

Pull Request Test Coverage Report for Build 9ae53f0f3464f3759d0395026ade684fc8ebac8b-PR-3339

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+3.9%) to 74.69%

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Totals
Change from base Build 5058122989783627b613cf25224f2592b71e7e4a:	3.9%
Covered Lines:	1986
Relevant Lines:	2659

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💛 - Coveralls