Migrate fee payment from Currency to fungible (#2292)

Part of https://github.com/paritytech/polkadot-sdk/issues/226 
Related https://github.com/paritytech/polkadot-sdk/issues/1833

- Deprecate `CurrencyAdapter` and introduce `FungibleAdapter`
- Deprecate `ToStakingPot` and replace usage with `ResolveTo`
- Required creating a new `StakingPotAccountId` struct that implements
`TypedGet` for the staking pot account ID
- Update parachain common utils `DealWithFees`, `ToAuthor` and
`AssetsToBlockAuthor` implementations to use `fungible`
- Update runtime XCM Weight Traders to use `ResolveTo` instead of
`ToStakingPot`
- Update runtime Transaction Payment pallets to use `FungibleAdapter`
instead of `CurrencyAdapter`
- [x] Blocked by https://github.com/paritytech/polkadot-sdk/pull/1296,
needs the `Unbalanced::decrease_balance` fix

polkadot/runtime/test-runtime/src/lib.rs

@@ -20,7 +20,7 @@
 // `construct_runtime!` does a lot of recursion and requires us to increase the limit to 256.
 #![recursion_limit = "256"]
 
-use pallet_transaction_payment::CurrencyAdapter;
+use pallet_transaction_payment::FungibleAdapter;
 use parity_scale_codec::Encode;
 use sp_std::{collections::btree_map::BTreeMap, prelude::*};
 
@@ -233,7 +233,7 @@ parameter_types! {
 
 impl pallet_transaction_payment::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	type OnChargeTransaction = CurrencyAdapter<Balances, ()>;
+	type OnChargeTransaction = FungibleAdapter<Balances, ()>;
 	type OperationalFeeMultiplier = OperationalFeeMultiplier;
 	type WeightToFee = WeightToFee;
 	type LengthToFee = frame_support::weights::ConstantMultiplier<Balance, TransactionByteFee>;