Utility: disable DirectoryMonitor on Windows temporarily

This temporarily disables the functionality on Windows to match the
Linux port.  We should be able to reimplement this functionality as
already done in clang and swift-tools-support-core on Windows.

Author: compnerd

Sources/SwiftDocCUtilities/Utility/DirectoryMonitor.swift

@@ -11,7 +11,7 @@
 import Foundation
 import SwiftDocC
 
-#if !os(Linux) && !os(Android)
+#if !os(Linux) && !os(Android) && !os(Windows)
 import Darwin
 
 /// A throttle object to filter events that come too fast.