conditionally_graphql! is no longer conditional

The version API used to run a GraphQL equivalent implementation or fallback on the old code if graphql was not enabled.

A helper function, conditionally_graphql!, was developed to check the feature flag.

Now that the feature flag was removed, conditionally_graphql! is no longer conditional and the fallback parameter is useless.

I suggest we rename conditionally_graphql! to run_graphql! and remove the fallback parameter

/cc @cablett