#23660 [Java] [vertx] Make supportVertxFuture compatible with vertx 5

Closes #23659

In vertx 5, Promise no longer extends Handler<AsyncResult>, which means we can't directly pass in a promise into an arg that accepts a handler. However, promise::handle still works, in both versions of vertx.

Also added a new sample java-vertx5-supportVertxFuture to the samples.

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@bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10) @martin-mfg (2023/08)

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Summary by cubic

Make supportVertxFuture compatible with Vert.x 5 by switching generated calls to promise::handle, keeping Vert.x 4 support. Adds a Vert.x 5 Petstore sample and updates CI to build it.

• Bug Fixes

  • In Java/libraries/vertx/api.mustache, use promise::handle in default Future helpers (and auth variants) instead of passing the Promise directly.
  • Update existing samples/client/petstore/java/vertx-supportVertxFuture APIs to use promise::handle.

• New Features

  • Add Vert.x 5 sample: samples/client/petstore/java/vertx5-supportVertxFuture with config bin/configs/java-vertx5-supportVertxFuture.yaml (useVertx5: "true", supportVertxFuture: "true").
  • CI: include the new sample in .github/workflows/samples-java-client-jdk11.yaml.