winrt: bumped SDL's shipping version number in winrtbuild.ps1

build-scripts/winrtbuild.ps1

@@ -39,7 +39,7 @@
 #
 
 # Base version of SDL, used for packaging purposes
-$SDLVersion = "2.0.4"
+$SDLVersion = "2.0.7"
 
 # Gets the .bat file that sets up an MSBuild environment, given one of
 # Visual Studio's, "PlatformToolset"s.