Pickle base fix

[jmensch1]

So in the last round I was trying to populate the picklebase before starting the server. It took longer than 60 seconds, so the server failed with an error:

Error R10 (Boot timeout) -> Web process failed to bind to $PORT within 60 seconds of launch

In this PR the server is started immediately, and the picklebase is populated in a separate process. A file called 'ready' is created when process finishes, which informs the Sanic workers that they can query the picklebase instead of the database.

• Up to date with dev branch
• Branch name follows guidelines
• All PR Status checks are successful
• Peer reviewed and approved

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