[macOS sandbox mode] Application group name mangling for semaphores

[DellaBitta]

Description

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

When macOS Sandbox mode is enabled, macOS requires that semaphores have a name that is prefixed by the App's Group Name. If the semaphore's name doesn't match this convention then its creation fails.

Unfortunately there's no official way for the SDK to query the app's group name at runtime, so we can't automatically mangle the semaphore names.

Instead I've updated the SDK to use an Info.plist property named FBAppGroupEntitlementName on macOS. If that property is present then the SDK will use it's value to prefix the semaphore names.

As an additional issue, the SDK attempted to detect semaphore creation errors by comparing the semaphore handle to nil. But in the case of macOS, a semaphore creation error returns SEM_FAILED which is 0xFFFFFFFFFFFFFFFF, not nil. And on Linux, sem_init returns -1. I've updated the corresponding platform implementations to detect the correct  values for these errors.

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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.

Integration Test
Packaging -> Integration Test

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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.

[jonsimantov]

Generally approved, but I had a few comments - it would be okay to address some in a followup.

[github-actions]

❌  Integration test FAILED

Requested by @DellaBitta on commit 3095517
Last updated: Wed Dec 21 10:39 PST 2022
View integration test log & download artifacts

Failures	Configs
gma	[TEST] [FAILURE] [Android] [1/3 os: macos] [1/2 android_device: android_target] (1 failed tests)   FirebaseGmaTest.TestRewardedAdStress [TEST] [FLAKINESS] [iOS] [macos] [1/2 ios_device: ios_target] (2 failed tests)   FirebaseGmaTest.TestRewardedAdLoad   FirebaseGmaTest.TestRewardedAdLoadEmptyRequest
messaging	[TEST] [FLAKINESS] [Android] [1/3 os: ubuntu] [1/2 android_device: android_target] (1 failed tests)   CRASH/TIMEOUT

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