Reduce NATS and Elastic PVC sizes based on usage (#1355)

Summary: These use fewer resources than expected mainly due to certain
fixes that were made.

Relevant Issues: N/A

Type of change: /kind cleanup

Test Plan: Deploy the new resources.

Signed-off-by: Vihang Mehta <vihang@pixielabs.ai>

Author: vihangm

k8s/cloud_deps/prod/elastic/elastic_storage_patch.yaml

@@ -11,7 +11,7 @@
 # Data node.
 - op: replace
   path: /spec/nodeSets/1/volumeClaimTemplates/0/spec/resources/requests/storage
-  value: 500Gi
+  value: 100Gi
 
 - op: add
   path: /spec/nodeSets/1/volumeClaimTemplates/0/spec/storageClassName

k8s/cloud_deps/prod/nats/storage_patch.yaml

@@ -13,4 +13,4 @@ spec:
       storageClassName: ssd
       resources:
         requests:
-          storage: 800Gi
+          storage: 200Gi