Use the `%target-swift-5.1-abi-triple` substitution to compile the tests for
deployment to the minimum OS versions required for use of _Concurrency APIs,
instead of disabling availability checking.
If a parameter is marked consuming and its type is Copyable, that
parameter has eager-move semantics. Apply that attribute to the
SILFunctionArgument corresponding to the parameter.
rdar://108385761