Fix blind keyed_account indexing in BPF and Move loader (#6810)

sdk/src/instruction.rs

@@ -73,6 +73,9 @@ pub enum InstructionError {
     /// A non-system program changed the size of the account data
     AccountDataSizeChanged,
 
+    /// the instruction expected an executable account
+    AccountNotExecutable,
+
     /// CustomError allows on-chain programs to implement program-specific error types and see
     /// them returned by the Solana runtime. A CustomError may be any type that is represented
     /// as or serialized to a u32 integer.