macos_platform_tests is timing out when built for all packages.

Examples:

https://ci.chromium.org/ui/p/flutter/builders/prod/Mac_arm64%20macos_platform_tests%20master%20-%20packages/1662
https://ci.chromium.org/ui/p/flutter/builders/prod/Mac_arm64%20macos_platform_tests%20master%20-%20packages/1659
https://ci.chromium.org/ui/p/flutter/builders/prod/Mac_arm64%20macos_platform_tests%20master%20-%20packages/1657

Can macos_platform_tests builder be broken apart? The native tests alone are taking ~40 minutes.