Update fuzzer manifest to prepare for replace_as_executable restrictions

BUG: SEC-310

Preflight to ensure introduction of the new ambient replace_as_executable
job policy restrictions.

Change-Id: Iedd3c9c13b58c996c763ee95991c9526fe1ee580
diff --git a/fuzzer.cmx b/fuzzer.cmx
index 722e6de..11a55b3 100644
--- a/fuzzer.cmx
+++ b/fuzzer.cmx
@@ -1,5 +1,8 @@
 {
     "sandbox": {
-        "features": [ "root-ssl-certificates" ]
+        "features": [
+            "root-ssl-certificates",
+            "deprecated-ambient-replace-as-executable"
+        ]
     }
 }