Remove old integration tests [ECR-3195]

[MakarovS]

Overview

Remove old integration tests that were replaced with TestKit tests.
In BlockchainIntegrationTest I didn't find any test cases that are not tested in new TestKit ITs. CoreSchema ITs are left as they are.

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See: https://jira.bf.local/browse/ECR-3195

Definition of Done

• There are no TODOs left in the code
• Change is covered by automated tests
• The coding guidelines are followed
• Public API has Javadoc
• Method preconditions are checked and documented in the Javadoc of the method
• Changelog is updated if needed (in case of notable or breaking changes)
• The continuous integration build passes

[coveralls]

Coverage decreased (-1.2%) to 85.457% when pulling 2481b21 on ECR-3195 into 22ba6d9 on master.

[dmitry-timofeev]

Coverage is not collected accross modules, hence the drop 🤷‍♂️

Possibly, it can be reconfigured.