Set params of core fellowship with the corrected value

The previous referendum set the params using the value from RFC50, which is annual salary. However, each payout cycle is configured to be 30 days. This means the value was incorrectly set to 12x the intended amount.

This proposal reduced the value by 12x.

Script to dry run this proposal: https://github.com/xlc/chopsticks-playground/blob/master/src/fellowship-params.ts

There are four members were registered in this payout cycle and will be / already paid with the incorrect parameters. However, due to the budget limitation, the exact payout is not 12x, but pro-rata reduced with the 100k cap.

Those four members can return the extra payment to the salary pallet account at AssetHub: 13w7NdvSR1Af8xsQTArDtZmVvjE8XhWNdL4yed3iFHrUNCnS

A suggestion was made to reduce the possibility of such mistake in future: https://github.com/paritytech/polkadot-sdk/issues/3617