`fillIn` treats text as html when the target is content editable

[rpemberton]

Example:

fillIn(contentEditableElement, '<div>foo</div>');

The text gets parsed as html though I'd expect it to be treated as text.

Should fillIn set textContent instead of innerHTML?

ember-test-helpers/addon/src/dom/fill-in.ts

Line 76 in 0505fdf

element.innerHTML = text;