I am currently trying to run tests on my Rails application (Rails 5.2.5, Ruby 2.7.3) and when I run the command bundle exec rake test teaspoon I get the following error...

Error: ReferenceError: Can't find variable: Intl

To try and resolve this, I have used npm install intl and yarn add intl, yet I still get the same error every time.

What steps need to be followed to resolve this error?