If this change is applied, the collators that are active will be determined about every 2 hours (`600 blocks * 12 sec/block = 2 hours`). In addition, reward calculation and payouts will also be done every 2 hours. Those two processes are very intense operations that the chain has to execute currently every 4 minutes, so making this change will unlock many resources for transactions. Other side effects are that decreasing the bonds or leaving the candidate set will increase to 4 hours. 
Changing the blocks per round to higher value is also mandatory to increase the active collator set size.
We decided to go with 2 hours based on the example of Moonriver, a parachain on Kusama whose organization created the *parachain-staking* pallet that is handling the `blocksPerRound` value.

Set blocks per round
- if called with `new` less than length of current round, will transition immediately
in the next block
- also updates per-round inflation config

- **Problem Statement:** 
  - Addressing the intensive operations of determining active collators and reward calculations every 4 minutes on the chain.
- **Significance:** 
  - Reducing the frequency of these operations to every 2 hours will free up resources for transactions.
- **Proposed Solution:** 
  - Change the collator determination and reward calculation frequency to every 2 hours.
- **Expected Outcomes:** 
  - Increased efficiency in resource allocation and transaction processing.

#5 Increase round duration to approximately 2 hours - external proposal 0x503be4