[play] Buffer for line numbering on editor on load.

[rgbkrk]

When initially server rendered, play has a little bit of a flicker while codemirror is loading up. We should make the initial display have a buffer for the line numbers (when the option is set).

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale[bot]]

This issue hasn't had any activity on it in the last 90 days. Unfortunately we don't get around to dealing with every issue that is opened. Instead of leaving issues open we're seeking to be transparent by closing issues that aren't being prioritized. If no other activity happens on this issue in one week, it will be closed. It's more than likely that just by me posting about this, the maintainers will take a closer look at these long forgotten issues to help evaluate what to do next. If you would like to see this issue get prioritized over others, there are multiple avenues 🗓:

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