How can Spock be made to retry failed Geb tests?
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I have functional tests for a Grails app which use Geb and Spock.  Occasionally, a functional test will fail for timeouts or other sporadic behavior. In previous projects using TestNG, I'd have a retryAnalyzer just trigger a retry during test execution to see if it fails both times (and then fail for real).

How do I get Spock to retry a failed test?