Update messaging aar path for Unity in CMake

[a-maurice]

Description

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

In the Messaging CMake we expose the path of the messaging aar for the Unity build to use. Because of the gradle update, the path changed slightly, so we need to update the path.

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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.

Building the Unity SDK locally, and on GHA.

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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 FAILED

Requested by @a-maurice on commit 5fead53
Last updated: Wed Jan 31 17:12 PST 2024
View integration test log & download artifacts

Failures	Configs
firestore	[BUILD] [ERROR] [MacOS] [x64] [openssl]
gma	[TEST] [FLAKINESS] [Android] [1/3 os: windows] [1/2 android_device: emulator_ftl_target] (1 failed tests)   CRASH/TIMEOUT
remote_config	[TEST] [FLAKINESS] [Android] [1/3 os: macos] [1/2 android_device: emulator_ftl_target] (1 failed tests)   CRASH/TIMEOUT
storage	[TEST] [FLAKINESS] [Android] [1/3 os: macos] [1/2 android_device: emulator_ftl_target] (1 failed tests)   CRASH/TIMEOUT

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