Use a ClassLoadingStrategy that is compatible with Java 17+

[cushon]

See "Supporting proxies on Java versions prior to 9 and past 10" in http://mydailyjava.blogspot.com/2018/04/jdk-11-and-proxies-in-world-past.html

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[cushon]

R: @kileys

[github-actions]

Stopping reviewer notifications for this pull request: review requested by someone other than the bot, ceding control

[kileys]

Run Java PreCommit

[kileys]

Run Java Dataflow V2 ValidatesRunner

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Run Dataflow ValidatesRunner Java 17

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Run Dataflow ValidatesRunner Java 11

[kileys]

This is the Java 11 jenkins job https://ci-beam.apache.org/job/beam_PostCommit_Java_ValidatesRunner_Dataflow_Java11_PR/19/

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Run Java PreCommit

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Run Java PreCommit