untangle syntax in intro.mdx (#1524)

Author: brandonzylstra

docs/intro.mdx

@@ -46,8 +46,7 @@ Testing Library encourages you to avoid testing
 [implementation details](https://kentcdodds.com/blog/testing-implementation-details)
 like the internals of a component you're testing (though it's still possible).
 [The Guiding Principles](/docs/guiding-principles) of this library emphasize a
-focus on tests that closely resemble how your web pages are interacted by the
-users.
+focus on tests that closely resemble how users interact with your web pages.
 
 You may want to avoid the following implementation details: