docs: Fix typo in volume topology zone match label

Source: https://kubernetes.io/docs/concepts/storage/storage-classes/#allowed-topologies

docs/parameters.md

@@ -53,7 +53,7 @@ allowedTopologies:
 - matchLabelExpressions:
   - key: topology.kubernetes.io/zone
     values:
-    - us-east-1
+    - us-east-1a
 ```
 
 Additionally, statically provisioned volumes can be restricted to pods in the appropriate Availability Zone, see the [static provisioning example](../examples/kubernetes/static-provisioning/).