Drop kubernetes 1.23.0 testing

Skip-Release-Notes

Change-Id: I49a0d9a27938dbf92d156bb73acf788eedcb040f
diff --git a/charts/charts_test.go b/charts/charts_test.go
index 233e6be..97be7d5 100644
--- a/charts/charts_test.go
+++ b/charts/charts_test.go
@@ -16,7 +16,6 @@
 
 var (
 	KUBERNETES_VERSIONS = []string{
-		"1.23.0",
 		"1.24.0",
 		"1.25.0",
 		"1.26.0",