bip54: fix off-by-one in creation date

Author: darosior

bip-0054.md

@@ -8,7 +8,7 @@
   Comments-URI: https://github.com/bitcoin/bips/wiki/Comments:BIP-0054
   Status: Draft
   Type: Standards Track
-  Created: 2024-04-11
+  Created: 2025-04-11
   License: CC0-1.0
 ```