## Description

In order to perform the migration from staking using `reserved` token to `locked` token (allowing to use staked tokens for Governance), new storage items were created to perform a lazy migration.

## Technical details

In order to avoid generating big PoV, the cleanup is split into batches which are scheduled to execute 1 block after the other.  
To better understand the keys being used:

encoded key details
```
xxHash(ParachainStaking): a686a3043d0adcf2fa655e57bc595a78
xxHash(DelegatorReserveToLockMigrations): 9b6d599e593dcb42496c51919687e13d
xxHash(CollatorReserveToLockMigrations): 8f5592b04d535b56f4b85ca2a5ed140c
```

## Verification

Script used https://github.com/PureStake/moonbeam-tools/blob/0cd51e0950bc4553801b97c1917324aaeab5970e/src/hotfixes/runtime-1900-fix-staking-reserve-to-lock-migration.ts

Command to verify: `ts-node src/hotfixes/runtime-1900-fix-staking-reserve-to-lock-migration.ts --url wss://wss.moonriver.moonbeam.network --at-block 2918208`

```
DelegatorReserveToLockMigrations:   6401 (prefix: 0xa686a3043d0adcf2fa655e57bc595a789b6d599e593dcb42496c51919687e13d)
 CollatorReserveToLockMigrations:     89 (prefix: 0xa686a3043d0adcf2fa655e57bc595a788f5592b04d535b56f4b85ca2a5ed140c)
Encoded proposal after schedule is 0x1e001000013901537461746520636c65616e75703a20436f6c6c61746f7252657365727665546f4c6f636b4d6967726174696f6e732073746f7261676520286b6579733a2031202d207375626b6579733a20383929000780a686a3043d0adcf2fa655e57bc595a788f5592b04d535b56f4b85ca2a5ed140c5900000000014501537461746520636c65616e75703a2044656c656761746f7252657365727665546f4c6f636b4d6967726174696f6e732073746f7261676520286b6579733a2031202d207375626b6579733a203634303129000780a686a3043d0adcf2fa655e57bc595a789b6d599e593dcb42496c51919687e13d01190000
Encoded proposal hash after schedule is 0x349095b73fb0123804ee98fef99291e6277df396447db72dde9580cadff510d0
Encoded length 498
```


Send a batch of dispatch calls.

May be called from any origin.

- `calls`: The calls to be dispatched from the same origin. The number of call must not
  exceed the constant: `batched_calls_limit` (available in constant metadata).

If origin is root then call are dispatch without checking origin filter. (This includes
bypassing `frame_system::Config::BaseCallFilter`).

# <weight>
- Complexity: O(C) where C is the number of calls to be batched.
# </weight>

This will return `Ok` in all circumstances. To determine the success of the batch, an
event is deposited. If a call failed and the batch was interrupted, then the
`BatchInterrupted` event is deposited, along with the number of successful calls made
and the error of the failed call. If all were successful, then the `BatchCompleted`
event is deposited.

- They are making changes to how staking works in Polkassembly.
- They created new storage items to help with the changes.
- They are doing the changes in batches to avoid problems.
- They used a script to verify the changes.
- The changes are quite technical and involve different keys and commands.

#118 Technical Cleanup: Remove reserve-to-lock lazy migration storage items