[2.9.x] Backport explicit supervision strategy setting (backport #12796) by @gwak

[mergify]

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Backport changes from #12794

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This is an automatic backport of pull request #12796 done by [Mergify](https://mergify.com).

[mkurz]

Scripted tests play-sbt-plugin/java-test-helpers fails for Scala 3 only

[info] [error] Test controllers.HomeControllerTest.testOnlyFormDataNoFiles failed: java.lang.NoSuchMethodError: 'akka.japi.function.Function akka.stream.Supervision$.resumingDecider()', took 0.095 sec

https://github.com/playframework/playframework/actions/runs/9876530330/job/27276693023?pr=12797#step:11:6318

[mkurz]

This is caused by the the current approach in the 2.9.x branch to use for3Use2_13 for Scala 3 when using akka-http. It remembers me of

• Akka throws exception on Websocket timeout when using Scala 3 #11928 (fixed by Avoid unapply because we mix Scala 3 and Scala 2.13 artifacts when using akka(-http) #11929)
• Scala 3 only: java.lang.NoSuchMethodError: ...TLSProtocol$SessionBytes$.unapply(...) apache/pekko-http#183 (fixed by avoid unapply due to issue reported by Play team (scala 3 only) apache/pekko-http#184)

Fortunately we can just use the getter method for now to avoid the error.