Create separate Sonar step in build (update to Java 17)

[Michael1993]

Closes #782

Proposed commit message:

Make SonarCloud job use Java 17 (#782 / #784)

SonarCloud is moving away from supporting Java 11.
This PR separates the job from the main build into its own step
and configures it to use Java 17.

Closes: #782
PR: #784

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