chore: update java version in intergration test runners

[AustinBenoit]

Description

Provide details of the change, and generalize the change in the PR title above.

Chore: Update Java version in workflow runners

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Testing

Describe how you've tested these changes.

Make sure the workflow runners continue to work.

Happy build https://github.com/firebase/firebase-unity-sdk/actions/runs/21655710929
Mostly happy test run: https://github.com/firebase/firebase-unity-sdk/actions/runs/21672261986

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Type of Change

Place an x the applicable box:

• Bug fix. Add the issue # below if applicable.
• New feature. A non-breaking change which adds functionality.
• Other, such as a build process or documentation change.

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[gemini-code-assist]

Note

Gemini is unable to generate a summary for this pull request due to the file types involved not being currently supported.

[github-actions]

❌  Integration test FAILED

Requested by @firebase-workflow-trigger[bot] on commit 00fd3f1
Last updated: Tue Feb 3 07:16 PST 2026
View integration test log & download artifacts

Failures	Configs
/Users/runner/work/firebase-unity-sdk/firebase-unity-sdk/testapps/Unity2021.3.43f1-NET4.6/FirebaseAI/testapp	[TEST] [ERROR] [2021] [1/2 Build OS(s): macos] [1/2 Platform(s): 14] [1/2 Test Device(s): Playmode]
D:\a\firebase-unity-sdk\firebase-unity-sdk\testapps\Unity2021.3.43f1-NET4.6\FirebaseAI\testapp	[TEST] [ERROR] [2021] [1/2 Build OS(s): windows] [1/2 Platform(s): Playmode] [1/2 Test Device(s): github_runner]