SIMD-0290 Relax Fee-Payer Constraint

Authors: Andrew Fitzgerald (Anza), Hanako Mumei (Anza)

This proposal aims to relax the handling of invalid fee-payers for blockhash transactions in Solana. Currently, if a transaction with an invalid fee-payer is included in a block, the entire block is rejected. This proposal suggests that instead of rejecting the entire block, the blockhash transaction with the invalid fee-payer should simply skip execution.