Increase snapshot perf target on AMD for 512mb

Signed-off-by: Matthew Schlebusch <schlebus@amazon.com>

Author: mattschlebusch

tests/integration_tests/performance/test_snapshot_perf.py

@@ -90,7 +90,7 @@
             "4.14": {
                 "sync": {
                     "2vcpu_256mb.json": {"target": 15},
-                    "2vcpu_512mb.json": {"target": 15},
+                    "2vcpu_512mb.json": {"target": 19},
                 }
             },
             "5.10": {