Refactor Quickstart component to prevent error

[john-rock]

What are you changing in this pull request and why?

Fixes the Node.removeChild: The node to be removed is not a child of this node error we were seeing when trying to use a Snippet with a nested component.

Additional information

The following code was setup to make sure that in the event a snippet that is nested under a step (##) in the quickstart markdown file contained an h2 (##) it would not be rendered as an additional step.

      snippetContainer.forEach((snippet) => {
        const parent = snippet?.parentNode;
        while (snippet?.firstChild && parent.className) {
          if (parent) {
            parent.insertBefore(snippet.firstChild, snippet);
          }
        }
      });

Since the update core quickstart contains a snippet in Step 8 <Snippet path="tutorial-sql-query" /> which contains a nested component <WHcode /> it was causing the component to break when building the steps.

This PR makes sure the component is fully loaded before attempting any manipulation on the steps.

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[runleonarun]

I am no longer seeing any errors! Thank you!