Registrar: Deposit covering max code size (#3020)

This PR implements phase 1 of:
https://github.com/paritytech/polkadot-sdk/pull/2372#discussion_r1461873933

NOTE: This means that all the current parachains can upgrade their code
to the maximum size for free.

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Co-authored-by: Bastian Köcher <[email protected]>
Co-authored-by: Radha <[email protected]>