feat: compute pallet/storage prefix hash at compile time (#1539)

Since the hash rules of this part of the `pallet_prefix/storage_prefix`
are always fixed, we can put the runtime calculation into compile time.

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polkadot address: 15ouFh2SHpGbHtDPsJ6cXQfes9Cx1gEFnJJsJVqPGzBSTudr

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Co-authored-by: Juan <[email protected]>
Co-authored-by: command-bot <>
Co-authored-by: Oliver Tale-Yazdi <[email protected]>