Change log-cache-reduce-memory ops file to extract log-cache from dop…

…pler

As part of the latest cf-deployment, [log-cache is no longer nested under doppler](cloudfoundry/cf-deployment#949)

Pipeline failure caused by the change:
```
operation [0] in ops-files/log-cache-reduce-memory.yml failed': Expected to find exactly one matching array item for path '/instance_groups/name=doppler/jobs/name=log-cache' but found 0
```

cf-deployment-operations/log-cache-reduce-memory.yml

@@ -1,3 +1,3 @@
 - type: replace
-  path: '/instance_groups/name=doppler/jobs/name=log-cache/properties/memory_limit_percent?'
+  path: '/instance_groups/name=log-cache/jobs/name=log-cache/properties/memory_limit_percent?'
   value: 25