Update Ironbank to v1.16.1

This MR contains the following updates:

Package	Update	Change
registry1.dso.mil/ironbank/opensource/istio/install-cni	minor	1.15.3 -> 1.16.1
registry1.dso.mil/ironbank/opensource/istio/pilot	minor	1.15.3 -> 1.16.1
registry1.dso.mil/ironbank/opensource/istio/proxyv2	minor	1.15.3 -> 1.16.1

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relates to #88 (closed)