Bot to update users stake

[nakul1010]

Describe the bug
The update_user_stake call needs to be periodically called when there is a significant change in the percentage of users' stake. This is crucial to ensure that Staking rewards are accurate for users.

Solution
To address this issue, follow these steps:

• Create an additional member in the workspace called stake_updater.

• Implement a loop to iterate through staked accounts.

• Within the loop, perform the following tasks:

  • Calculate both the initial and final rewards for each account.
  • Check if the difference between the initial and final rewards exceeds a certain threshold (X%).
    If the difference is greater than the specified threshold, invoke the update_user_stake extrinsic to update the user's stake.

Additional context
InterBtc side PR 1097