Fix robot-simulator tests in groovy-test-runner

[artamonovkirill]

Fixes "src/test/groovy/RobotSimulatorSpec.groovy: 5: unable to resolve class Stepwise for annotation":

Since groovy-test-running imports Stepwise annotation, a wild-card or spock.lang.Stepwise import is required.
Opted for a wild-card option as this is how it was prior to #461

[github-actions]

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[github-actions]

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