Update the Liquid asset registry pubkey (#568)

Same key (A1DF83770F29548228170D63DBABBA3AD525ACA1),
with the expiry date extended (2025-06-01 -> 2027-06-01).

Co-authored-by: Kevin Marcelo <kmarcelo@blockstream.com>

Author: kevinmarceloph

contrib/asset_registry_pubkey.asc

@@ -2,8 +2,8 @@
 
 mDMEXO8+ZRYJKwYBBAHaRw8BAQdAuOmTOyYQvFquAX5qAwgzuyrK7z3OAJfqxi44
 dHobhiq0GSAoTGlxdWlkIHJlZ2lzdHJ5IGFzc2V0cymIlgQTFggAPgIbAwULCQgH
-AgYVCAkKCwIEFgIDAQIeAQIXgBYhBKHfg3cPKVSCKBcNY9urujrVJayhBQJkef9W
-BQkLTSfxAAoJENurujrVJayhDYEBAIV/jqMmu6hg+A+NuphcHsYjPImcNijqS9BB
-LPxOvottAQDE2Ouh6+Lbr+yRQLPlV5OdZFD1vhrwQNjevr1w+E2QDw==
-=v+Fd
+AgYVCAkKCwIEFgIDAQIeAQIXgBYhBKHfg3cPKVSCKBcNY9urujrVJayhBQJoLpk+
+BQkPDvDZAAoJENurujrVJayhATkA/1KJUequVNe4j3SHBorCPgDTi6tAPqOcdYNA
+vg6u2G44AP0R+2PnBjJ1FDallgUbhgGl0cDyPKBgjXl5R4M+WDN9Cg==
+=PW6p
 -----END PGP PUBLIC KEY BLOCK-----