change the error message to the warning one in XCodeProjectPathcer.cs (#754)

In previous versions, an error message was displayed when doing an iOS build on Windows OS. However, since Unity allows iOS xcodeproj to be built on Windows OS, such a message should at least be displayed as a warning, not an error.

Co-authored-by: a-maurice <[email protected]>

Author: TP-113

editor/app/src/XcodeProjectPatcher.cs

@@ -173,7 +173,7 @@ private static void CheckBuildEnvironment() {
         BuildTarget buildTarget = EditorUserBuildSettings.activeBuildTarget;
         if ((buildTarget == BuildTarget.iOS || buildTarget == BuildTarget.tvOS) &&
             Application.platform == RuntimePlatform.WindowsEditor) {
-            Debug.LogError(DocRef.IOSNotSupportedOnWindows);
+            Debug.LogWarning(DocRef.IOSNotSupportedOnWindows);
         }
     }