Add some debug code

Author: cachemeifyoucan

Tests/SwiftDriverTests/ToolchainTests.swift

@@ -193,7 +193,7 @@ import CRT
         try fs.createSymbolicLink(anotherSwiftFrontend, pointingAt: defaultSwiftFrontend, relative: false)
 
         // test if SWIFT_DRIVER_TOOLNAME_EXEC is respected
-        do {
+        #expect(throws: Never.self) {
           var driver = try Driver.forTesting(args: ["swiftc", "-print-target-info"],
                                   env: [PATH: ProcessEnv.path!,
                                         SWIFT_FRONTEND_EXEC: customSwiftFrontend.pathString,
@@ -205,7 +205,7 @@ import CRT
         }
 
         // test if tools directory is respected
-        do {
+        #expect(throws: Never.self) {
           var driver = try Driver.forTesting(args: ["swiftc", "-print-target-info", "-tools-directory", toolsDirectory.pathString],
                                   env: [PATH: tempDirectory.pathString, SWIFT_SCANNER_LIB: customSwiftScan.pathString],
                                   fileSystem: fs)
@@ -215,7 +215,7 @@ import CRT
         }
 
         // test if current working directory is searched before PATH
-        do {
+        #expect(throws: Never.self) {
 #if os(Windows)
           let separator = ";"
 #else