update test snapshot to protocol 27

Author: leighmcculloch

soroban-sdk/test_snapshots/tests/snapshot_source_empty_wasm_hash/test_empty_wasm_hash_not_requested_from_snapshot_source.1.json

@@ -8,7 +8,7 @@
     []
   ],
   "ledger": {
-    "protocol_version": 26,
+    "protocol_version": 27,
     "sequence_number": 0,
     "timestamp": 0,
     "network_id": "0000000000000000000000000000000000000000000000000000000000000000",