Update Ironbank

This MR contains the following updates:

Package	Update	Change
registry1.dso.mil/ironbank/opensource/kubernetes/kubectl	patch	v1.28.3 -> v1.28.4
registry1.dso.mil/ironbank/redhat/ubi/ubi8-minimal	minor	8.8 -> 8.9

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chart/tests/manifests/disallow-deprecated-apis.yaml

@@ -21,4 +21,4 @@ spec:
       subjects:
         - kind: Group
           group:
-            name: "system:unauthenticated"
\ No newline at end of file
+            name: "system:unauthenticated"