Reland "[Darwin] Disable NSAsserts in release builds. #860"

[hellohuanlin]

Need to make sure this doesn't fail the CI for engine repo.

List which issues are fixed by this PR. You must list at least one issue.

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[hellohuanlin]

Need to make sure this doesn't fail the CI for engine repo.

[hellohuanlin]

This is still pending the other build to pass. Let me convert it to draft

[goderbauer]

(triage): I am going to close this one since after the mono-repo merge the buildroot is now part of the regular flutter/flutter repository. If this change is still needed, please open a new PR on flutter/flutter. Thank you.