API test rely on minor SDK version

[ForNeVeR]

Consider this test failure: it has failed because of a minor change somewhere:

Index: Clipboard.txt
===================================================================
diff --git a/Clipboard.txt b/scratch_1.txt
rename from Clipboard.txt
rename to scratch_1.txt
--- a/Clipboard.txt 
+++ b/scratch_1.txt 
@@ -37,10 +37,10 @@
         public int SelectionLength { get { throw null; } set { } }
         public int SelectionStart { get { throw null; } set { } }
         public string SystemTextFontName { get { throw null; } set { } }
-        [System.CodeDom.Compiler.GeneratedCodeAttribute("PresentationBuildTasks", "7.0.2.0")]
+        [System.CodeDom.Compiler.GeneratedCodeAttribute("PresentationBuildTasks", "7.0.3.0")]
         [System.Diagnostics.DebuggerNonUserCodeAttribute]
         public void InitializeComponent() { }
-        [System.CodeDom.Compiler.GeneratedCodeAttribute("PresentationBuildTasks", "7.0.2.0")]
+        [System.CodeDom.Compiler.GeneratedCodeAttribute("PresentationBuildTasks", "7.0.3.0")]
         [System.ComponentModel.EditorBrowsableAttribute(1)]
         [System.Diagnostics.DebuggerNonUserCodeAttribute]
         void System.Windows.Markup.IComponentConnector.Connect(int connectionId, object target) { }
@@ -136,4 +136,4 @@
         public static System.Windows.Media.Imaging.BitmapSource RenderToBitmap(this XamlMath.TexFormula formula, XamlMath.TexEnvironment environment, double scale = 20, double x = 0, double y = 0, double dpi = 96) { throw null; }
         public static System.Windows.Media.Geometry RenderToGeometry(this XamlMath.TexFormula formula, XamlMath.TexEnvironment environment, double scale = 20, double x = 0, double y = 0) { throw null; }
     }
-}
+}
\ No newline at end of file

We should make the test infrastructure more robust towards this kind of change.