Test: Fix availability in a79aa9924bdc378.swift.

Author: tshortli

validation-test/compiler_crashers_2/a79aa9924bdc378.swift

@@ -1,6 +1,6 @@
 // {"kind":"emit-silgen","original":"941ad66b","signature":"swift::CanTypeWrapperTraits<swift::ReferenceStorageType>::type swift::SILType::castTo<swift::ReferenceStorageType>() const","signatureAssert":"Assertion failed: (isa<To>(Val) && \"cast<Ty>() argument of incompatible type!\"), function cast"}
 // RUN: not --crash %target-swift-frontend -emit-silgen %s
-@available(macOS 14.0, *)
+@available(SwiftStdlib 5.9, *)
 struct a<each b> {
   var c: (repeat each b) {
     (repeat {