Update article.md

"That's not a function" -> "It's not a function"

Author: paroche

1-js/13-modules/03-modules-dynamic-imports/article.md

@@ -94,5 +94,5 @@ Dynamic imports work in regular scripts, they don't require `script type="module
 ```smart
 Although `import()` looks like a function call, it's a special syntax that just happens to use parentheses (similar to `super()`).
 
-So we can't copy `import` to a variable or use `call/apply` with it. That's not a function.
+So we can't copy `import` to a variable or use `call/apply` with it. It's not a function.
 ```