Add Java setup to Windows x64 QNN CI Pipeline (#29754)
### Description
Copies the Java setup step from sibling files `windows_webgpu.yml`,
`windows_x64_release_xnnpack.yml`,
`windows_x64_release_build_x64_release.yml` to `windows_qnn_x64.yml`.
This explicitly ensures a compatible Java version, rather than relying
on the JDK already installed on the self-hosted runner. Otherwise there
may be breakages when switching the runner.
### Motivation and Context
I believe this will fix the failures in CI for the Windows x64 QNN CI
Pipeline. I'm seeing it fail in both an unrelated PR:
https://github.com/microsoft/onnxruntime/pull/29728
https://github.com/microsoft/onnxruntime/actions/runs/29509983398/job/87780661649?pr=29728
and in commits to main:
https://github.com/microsoft/onnxruntime/actions/runs/29546572913/job/87780090142
https://github.com/microsoft/onnxruntime/actions/runs/29499730505/job/87625355397
This is assuming the chain of causation:
1. https://github.com/microsoft/onnxruntime/pull/29731 switches the
runner pool
2. The `windows_qnn_x64.yml` pipeline finds JDK 8 already on the runner
(previous runner pool had JDK 11)
3. The Spotless Gradle plugin v7.2.1 isn't compatible with JDK 8
4. onnxruntime Java project can't be configured
5. Build fails
This new workflow action hopefully installs a compatible JDK & all will
be well.
https://github.com/microsoft/onnxruntime/issues/29753
