Update mod_tracing.rb feature capitalization

The feature is: `IIS-HttpTracing` per: https://docs.microsoft.com/en-us/iis/install/installing-iis-7/understanding-setup-in-iis  

Thus this fails on windows versions that have case sensitive feature installation (windows 7 for example).

recipes/mod_tracing.rb

@@ -23,7 +23,7 @@
 feature = if Opscode::IIS::Helper.older_than_windows2008r2?
             'Web-Http-Tracing'
           else
-            'IIS-HTTPTracing'
+            'IIS-HttpTracing'
           end
 
 windows_feature feature do