linting fix

Signed-off-by: Corey Hemminger <hemminger@hotmail.com>

Author: Stromweld

spec/unit/mixlib/install/generator_spec.rb

@@ -482,7 +482,7 @@
         end
 
         it "constructs chef-ice metadata URL with m, p, pm parameters" do
-          expect(install_script).to include('$metadata_array = (')
+          expect(install_script).to include("$metadata_array = (")
           expect(install_script).to include('"?v=$($version)"')
           expect(install_script).to include('"license_id=$license_id"')
           expect(install_script).to include('"m=$architecture"')