Fix reconciliation comparisons when there are no NSGs (#329)

* Fix reconciliation comparisons when there are no NSGs

Author: shyamradhakrishnan

SECURITY.md

@@ -21,7 +21,7 @@ security features are welcome on GitHub Issues.
 
 Security updates will be released on a regular cadence. Many of our projects
 will typically release security fixes in conjunction with the
-[Oracle Critical Patch Update][3] program. Additional
+Oracle Critical Patch Update program. Additional
 information, including past advisories, is available on our [security alerts][4]
 page.
 

cloud/scope/util.go

@@ -26,6 +26,9 @@ const (
 
 // GetNsgNamesFromId returns the names of the NSGs with the provided IDs
 func GetNsgNamesFromId(ids []string, nsgs []*infrastructurev1beta2.NSG) []string {
+	if len(ids) == 0 {
+		return nil
+	}
 	names := make([]string, 0)
 	for _, id := range ids {
 		for _, nsg := range nsgs {