ES6: Create Strings using Template Literals not detecting my use of template strings

I’m having some trouble on this challenge. My first mind went to doing this

const resultDisplayArray = arr.map(entry => {
    return`<li class="text-warning">${entry}</li>`;
  });

but I got the error

Invalid regular expression flags

and the

Template strings were used

rule doesn’t pass.

I also tried changing the “const” to “let” setting it to an empty array and pushing to it with “map”, “forEach” and a regular “for” loop. Each time in my console I got the array of items we’re suppose to get, but that rule never passes. Why is this?