Fix variable names:

[dmitry-timofeev]

'list', not 'set'

Overview

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

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 remained the same at 85.672% when pulling 79f0656 on dmitry-timofeev:fix-var-names into 82f29f7 on exonum:master.