Function getDecreaseAdditionalValidatorStakeInstruction

(Staker only) Decrease active stake again from a validator, eventually moving it to the reserve Works regardless if the transient stake account already exists. Internally, this instruction:

• withdraws rent-exempt reserve lamports from the reserve into the ephemeral stake
• splits a validator stake account into an ephemeral stake account
• deactivates the ephemeral account
• merges or splits the ephemeral account into the transient stake account delegated to the appropriate validator The amount of lamports to move must be at least max(crate::MINIMUM_ACTIVE_STAKE, solana_program::stake::tools::get_minimum_delegation()).

0. [] Stake pool
1. [s] Stake pool staker
2. [] Stake pool withdraw authority
3. [w] Validator list
4. [w] Reserve stake account, to fund rent exempt reserve
5. [w] Canonical stake account to split from
6. [w] Uninitialized ephemeral stake account to receive stake
7. [w] Transient stake account
8. [] Clock sysvar
9. '[]' Stake history sysvar
10. [] System program
11. [] Stake program