Migrate from Reserve & Lock to Holding & Freeze usage

[Dinonard]

As part of this PR, Currency trait has been deprecated, as has usage of Reserves and Locks.

There are two of Astar pallets which rely on locked & reservable currency:

• pallet_dapps_staking
• pallet_collator_selection

As part of this item, usage of LockableCurrency and ReservableCurrency should be replaced with usage of Holds and Freezes, without impacting existing functionality.

[github-actions]

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[Dinonard]

No need to do it since it's only one pallet and lock hasn't been deprecated.
We can easily do it once this actually happens.