Assert the blog page does (or does not) show a tag, as a link to its listing (/<blog>/tag/<tag>): the tag filter of a listing, or the tags of a post.
Examples
Then the blog should have the tag "Testing"
And the blog should have the tag "HubSpot"
Then the blog post should be tagged "Testing"
But the blog post should not be tagged "Marketing"
Then blog should not have the tag "Finance"
Pattern
Then(/^(?:the )?blog(?: post)? should( not)* (?:have the tag|be tagged) "([^"]*)"$/, …)
Part of @webship-js/hubspot-cms-steps (github.com/webship/hubspot-cms-steps), a step pack for Webship-js 2.0.x.