Default OAuth clients are no longer populated in MySQL

[rfk]

Back when oauth-server was a separate thing, it would automatically populate MySQL with a suite of default OAuth clients based on the definitions in this config file.

Now that it's been merged into the main auth-server repo, that config file is ignored. The list of default OAuth clients is instead taken from oauthServer.clients in the auth-server config, which defaults to empty. Thus, a newly-built fxa-dev environment does not contain OAuth client ids for Firefox Desktop, Fenix, or even the fxa-content-server itself. This makes it basically non-functional - you can sign in, but you can't use the account in any of our browsers or even access the settings page.

I briefly looked into porting the list above over to auth-server, but auth-server is currently configured via env vars rather than a config file, and I did not feel like serializing the current list of clients into a big ol' JSON string to stuff into the environment. Sorry. I'm going to manually populate the db with the records I need and file this issue for future reference.