inline prop is not available from React Markdown since 9.0.0

[AVGVSTVS96]

This is a really cool project, I was looking through the code and noticed that you're using the inline prop in combination with isCodeBlock to determine if code is inline. I ran into this issue when implementing syntax highlighting in my own chat project, inline was removed in 9.0.0, using isCodeBlock alone should be enough to cover most cases, but what I did in my project was write a rehype plugin to add the inline prop if the parent div isn't a pre element:

export function rehypeInlineCodeProperty() {
  return function (tree: Root): undefined {
    visit(tree, 'element', function (node: Element, _index, parent: Element) {
      if (parent && parent.tagName === 'pre') {
        node.properties.inline = false;
      } else {
        node.properties.inline = true;
      }
    });
  }
}

I think isCodeBlock is fine on it's own, but adding this rehype plugin could help cover edge cases. I'd be happy to make a PR if you want to go this direction, at the very least we can remove inline.

Reproduce: Add console.log(inline) and see that it's value is undefined when inline code is rendered.