Use identifier to return a path for desired template.

[anule]

Rails 6 no longer returns a path when inspecting an Action View template, which causes the style guide pages to break in Rails 6 apps. This change addresses that and restores access to the Honeycrisp pages.

[luigi]

Does this fix make the styleguide pages available in a Rails 6 app?

[anule]

Does this fix make the styleguide pages available in a Rails 6 app?

@luigi Yes. Though, there are some additional changes we had to make in the DAFI codebase to make it work fully. Renaming as a draft PR for now while I document those changes. Turns out those changes were unique to our code, so it should work more generally. You may have to do some extra configuration, but those changes should be suggested in the error screen when visiting $APP/cfa/styleguide

[SymonneSingleton]

Laura and I verified that this PR works on CMR's illinois-petition-service, which uses Rails 6 as well. Looks good to us! We did have to add link calfresh_logo.png to our manifest.js, which was suggested in the rails error.