Fix Flaky annotation for JUnit5 forked tests

[sarahchen6]

What Does This Do

Fix @Flaky annotation that is not working on JUnit 5 forked tests by triggering useJUnitPlatform() for forked tests before the @Flaky annotation is assessed here: https://github.com/DataDog/dd-trace-java/blob/master/buildSrc/src/main/kotlin/dd-trace-java.configure-tests.gradle.kts#L107

Motivation

@Flaky-annotated forked tests should only run flaky test jobs

Additional Notes

I tested this fix with a flaky-annotated failing test in dd-trace-core/src/test/java/datadog/trace/core/scopemanager/IterationSpansForkedTest.java.

• Flaky forked test with no fix fails: 0b43e2b, CI/CD Explorer, test example that failed
• Flaky forked test with fix succeeds: d264320, CI/CD Explorer, same test example that passes

Contributor Checklist

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Jira ticket: [PROJ-IDENT]

[datadog-official]

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 58.65% (-0.01%)

_{This comment will be updated automatically if new data arrives.
🔗 Commit SHA: 462514f | Docs | View more details | Give us feedback!}

[dd-octo-sts]

🟢 Java Benchmark SLOs — All performance SLOs passed

Suite	Status
Startup	🟢 pass

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	14.78 s	14.73 s	[-0.5%; +1.2%] (no difference)
startup:insecure-bank:tracing:Agent	13.60 s	13.71 s	[-1.4%; -0.1%] (maybe better)
startup:petclinic:appsec:Agent	16.86 s	16.82 s	[-0.6%; +1.1%] (no difference)
startup:petclinic:iast:Agent	16.85 s	16.93 s	[-1.3%; +0.3%] (no difference)
startup:petclinic:profiling:Agent	16.56 s	16.75 s	[-2.3%; +0.0%] (no difference)
startup:petclinic:sca:Agent	16.71 s	16.51 s	[+0.5%; +1.9%] (maybe worse)
startup:petclinic:tracing:Agent	16.00 s	16.34 s	[-3.1%; -1.1%] (significantly better)

Commit: 462514fd · CI Pipeline · Benchmarking Platform UI

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Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.

[dd-octo-sts]

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