Switch to a more generic method to get a server timestamp for mobile tests.

[jonsimantov]

Description

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

Because FTL devices can occasionally have the wrong locally set date, change the tests to fetch time from a publicly-accessible server. If it fails at any point, falls back to local device time.

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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.

You can see the remote timestamp in the test run 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 FAILED

Requested by @jonsimantov on commit 1c76fd3
Last updated: Mon Feb 12 16:46 PST 2024
View integration test log & download artifacts

Failures	Configs
missing_log	[TEST] [ERROR] [Android] [All 3 os] [1/2 android_device: android_target]
firestore	[TEST] [FLAKINESS] [iOS] [macos] [1/2 ios_device: ios_target] (1 failed tests)   AggregateCountTest.TestUnaryFilterQueries
installations	[TEST] [FLAKINESS] [iOS] [macos] [1/2 ios_device: ios_target] (1 failed tests)   FirebaseInstallationsTest.TestCanGetToken
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