Set up Portfolio Functional Tests (#2721)

Update portfolio functional tests and update
portfolio test snapshots through updatetest.

Author: gerteck

packages/cli/test/functional/testSites.js

@@ -14,6 +14,7 @@ const testTemplateSites = [
   'minimal,test_site_templates/test_minimal',
   'default,test_site_templates/test_default',
   'project,test_site_templates/test_project',
+  'portfolio,test_site_templates/test_portfolio',
 ];
 
 // These files will be generated within test_site/expected/