[xcm-emulator] Redo Parachain init (#1356)

* bring back proper init

* refactor block cycle

* ".git/.scripts/commands/fmt/fmt.sh"

* Update cumulus/xcm/xcm-emulator/src/lib.rs

Co-authored-by: Squirrel <[email protected]>

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Co-authored-by: command-bot <>
Co-authored-by: Giles Cope <[email protected]>