Downgrade CMake to 3.31.x on our runners.

[jonsimantov]

Description

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

GitHub runners updated CMake to CMake 4, which breaks our build. Install an explicit version of CMake instead.

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Testing

Describe how you've tested these changes. Link any manually triggered Integration tests or CPP binary SDK Packaging Github Action workflows, if applicable.

Tests/checks here and packaging workflow here.

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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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Notes

• Bug fixes and feature changes require an update to the Release Notes section of release_build_files/readme.md.
• Read the contribution guidelines CONTRIBUTING.md.
• Changes to the public API require an internal API review. If you'd like to help us make Firebase APIs better, please propose your change in a feature request so that we can discuss it together.

[github-actions]

Integration test with FLAKINESS (succeeded after retry)

Requested by @jonsimantov on commit 8dee6fe
Last updated: Wed Apr 2 18:43 PDT 2025
View integration test log & download artifacts

Failures	Configs
app_check	[TEST] [FLAKINESS] [Android] [1/3 os: ubuntu] [1/2 android_device: android_target] (1 failed tests)   CRASH/TIMEOUT
auth	[TEST] [FLAKINESS] [Android] [1/3 os: macos] [1/2 android_device: android_target] (1 failed tests)   CRASH/TIMEOUT
firestore	[TEST] [FLAKINESS] [Android] [1/3 os: macos] [1/2 android_device: emulator_ftl_target] (1 failed tests)   FirestoreTest.AuthWorks

Add flaky tests to go/fpl-cpp-flake-tracker