Temporarily disable deleteProberData cron job in sandbox for load-testing

Loadtesting data is identified as "prober data" by this job (it removes
anything under ".test", not only prober data)

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=177309096

java/google/registry/env/sandbox/default/WEB-INF/cron.xml

@@ -113,6 +113,9 @@
     <target>backend</target>
   </cron>
 
+  <!--
+    Removed for the duration of load testing
+    TODO(b/67947699): Restore after loadtesting is done
   <cron>
     <url><![CDATA[/_dr/cron/fanout?queue=retryable-cron-tasks&endpoint=/_dr/task/deleteProberData&runInEmpty]]></url>
     <description>
@@ -122,6 +125,7 @@
     <timezone>UTC</timezone>
     <target>backend</target>
   </cron>
+  -->
 
   <cron>
     <url><![CDATA[/_dr/cron/fanout?queue=retryable-cron-tasks&endpoint=/_dr/task/verifyEntityIntegrity&runInEmpty]]></url>