Fix build failure when building with pre-6.2 toolchain due to unrecognized `unsafe` keyword#1093

stmontgomery merged 1 commit intoswiftlang:mainswiftlang/swift-testing:mainfrom

stmontgomery:fix-6.1-unsafe-keyword-usagestmontgomery/swift-testing:fix-6.1-unsafe-keyword-usageCopy head branch name to clipboard