make short_filename public to not test a private method

Author: grosser

lib/code_climate/test_reporter/formatter.rb

@@ -36,6 +36,13 @@ def format(result)
         false
       end
 
+      # actually private ...
+      def short_filename(filename)
+        return filename unless ::SimpleCov.root
+        filename = filename.gsub(::SimpleCov.root, '.').gsub(/^\.\//, '')
+        apply_prefix filename
+      end
+
     private
 
       def partial?
@@ -83,12 +90,6 @@ def to_payload(result)
         }
       end
 
-      def short_filename(filename)
-        return filename unless ::SimpleCov.root
-        filename = filename.gsub(::SimpleCov.root, '.').gsub(/^\.\//, '')
-        apply_prefix filename
-      end
-
       def tddium?
         ci_service_data && ci_service_data[:name] == "tddium"
       end