reverted testing check

Author: sstadelman

Sources/Commands/SwiftTool.swift

@@ -575,8 +575,8 @@ public class SwiftTool<Options: ToolOptions> {
             #if os(macOS)
             if #available(macOS 10.13, *) {
              // ok, check succeeds
-                diagnostics.emit(error: "--netrc-file option is only supported on macOS >=10.13")
             } else {
+                diagnostics.emit(error: "--netrc-file option is only supported on macOS >=10.13")
             }
             #else
             diagnostics.emit(error: "--netrc-file option is only supported on macOS >=10.13")