Update EIP-8081: add EIP-8188

Merged by EIP-Bot.

Author: weiihann

EIPS/eip-8081.md

@@ -33,6 +33,7 @@ Definitions for `Scheduled for Inclusion`, `Considered for Inclusion`, `Declined
 * [EIP-4758](./eip-4758.md): Deactivate SELFDESTRUCT
 * [EIP-7716](./eip-7716.md): Anti-correlation attestation penalties
 * [EIP-8205](./eip-8205.md): Withdrawal credentials preregistration
+* [EIP-8188](./eip-8188.md): State Tiering by Write Age
 
 ### Activation