Prevent partition-exports entry from OSS usage

Validation was added on the config entry kind since that is called when
validating config entries to bootstrap via agent configuration and when
applying entries via the config RPC endpoint.

agent/structs/config_entry_exports.go

@@ -113,7 +113,12 @@ func (e *PartitionExportsConfigEntry) Validate() error {
 		return fmt.Errorf("partition-exports Name must be the name of a partition, and not a wildcard")
 	}
 
-	validationErr := validateConfigEntryMeta(e.Meta)
+	if err := requireEnterprise(e.GetKind()); err != nil {
+		return err
+	}
+	if err := validateConfigEntryMeta(e.Meta); err != nil {
+		return err
+	}
 
 	for _, svc := range e.Services {
 		if svc.Name == "" {
@@ -128,8 +133,7 @@ func (e *PartitionExportsConfigEntry) Validate() error {
 			}
 		}
 	}
-
-	return validationErr
+	return nil
 }
 
 func (e *PartitionExportsConfigEntry) CanRead(authz acl.Authorizer) bool {

agent/structs/config_entry_oss.go

@@ -35,3 +35,7 @@ func validateUnusedKeys(unused []string) error {
 func validateInnerEnterpriseMeta(_, _ *EnterpriseMeta) error {
 	return nil
 }
+
+func requireEnterprise(kind string) error {
+	return fmt.Errorf("Config entry kind %q requires Consul Enterprise", kind)
+}