`lily migrate` can use `--storage` arg instead of `--db` and `--schema`

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Description

Typically when deploying Lily, a config.toml is created to setup persistence targets for jobs via the --storage arg (which is the only way to configure persistence options on a Job. This is inconsistent with lily migrate which require --db and --schema flags. As a suggested UX improvement, it would good to make lily migrate --storage the default interaction and deprecate the old flags.

Acceptance criteria

• Storage options passed in as lily migrate --storage=TARGET instead of lily migrate --db=LONGCONNECTIONSTRING --schema=SCHEMANAME.

Where to begin

• Add --storage
• Deprecate --db and --schema with notice while still respecting their values

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FWIW, this is very low priority for me.