re-enable Sonarcloud after switchover to Github actions

[vladak]

In Travis configuration there used to be encrypted token.

[vladak]

Also, should be possible to enable it for the PRs: https://github.com/SonarSource/sonarcloud-github-action

[vladak]

Also, should be possible to enable it for the PRs: https://github.com/SonarSource/sonarcloud-github-action

actually, this one should not be used when using Maven.